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Home >> Ford >> 2004 >> Explorer Sport Trac 4D Utility >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Pinpoint Test QB: DTCS P0603 Or P1633: Keep Alive Power Through Pinpoint Test Z: Intermittent - CNG, Flex-Fuel & Gasoline >> Pinpoint Test X: Constant Control Relay Module (CCRM) >> Test Procedure
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Test Procedure

  1. X1 CHECK FOR AN OPEN VPWR CIRCUIT IN THE HARNESS 
    • PCM connector disconnected.
    • CCRM connector disconnected.
    • Measure the resistance between:
    ( + ) PCM Connector, Harness Side ( - ) CCRM Connector, Harness Side
    VPWR VPWR

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  X2. REPAIR the open circuit.
  2. X2 CHECK THE BATT+ AND IGN START/RUN VOLTAGE TO CCRM 
    • Key in ON position.
    • Measure the voltage between:
    ( + ) CCRM Connector, Harness Side ( - )
    B+ Ground
    IGN START/RUN Ground

    Are the voltages greater than 10.5 V? 

    Yes No
    Key in OFF position
    GO to  X3.    		 REPAIR the open circuit
    There is a B+ or IGN START/RUN circuit fault
    CHECK the condition of the related fuse(s)/diode. If OK, REPAIR the open circuit. If the fuse is damaged, check the IGN START/RUN or B+ and VPWR circuits for a short to ground before replacing.
  3. X3 CHECK THE GROUND CIRCUIT TO CCRM 
    • Measure the voltage between:
    ( + ) CCRM Connector, Harness Side ( - ) CCRM Connector, Harness Side
    B+ GND

    Is the voltage greater than 10.5 V? 

    Yes No
    INSTALL a new CCRM. REPAIR the open circuit.
  4. X4 DTCS P1479 OR P0481: CHECK THE HFC RELAY COIL RESISTANCE IN THE CCRM 
    NOTE: For one-speed fan applications, disregard DTC P1479/P0481.
    • CCRM connector disconnected.
    • Measure the resistance between:
    ( + ) CCRM Connector, Component Side ( - ) CCRM Connector, Component Side
    VPWR HFC

    Is the resistance between 65 ohms - 110 ohms? 

    Yes No
    GO to  X5. INSTALL a new CCRM.
  5. X5 CHECK THE CCRM FOR INTERNAL SHORTS 
    • Measure the resistance between:
    ( + ) CCRM Connector, Component Side ( - ) CCRM Connector, Component Side
    HFC IGN START/RUN
    HFC B+ (A)
    HFC B+ (B)
    HFC B+ (C)
    HFC B+ (D)
    HFC FPDM PWR
    HFC LFPWR
    HFC CCRM Case
    HFC FPDM PWR
    HFC A/CC GND
    HFC GND

    Are the resistances greater than 1K ohms? 

    Yes No
    GO to  X6. INSTALL a new CCRM.
  6. X6 CHECK THE PCM AND HFC CIRCUIT 
    • Connect a non-powered test lamp between:
    ( + ) CCRM Connector, Harness Side ( - )
    HFC Ground
    • Enter Output Test Mode. Refer to OUTPUT TEST MODE .
    • Command the high speed fan ON.
    • Command the outputs OFF.

    Does the test lamp turn on and off when the output(s) is commanded on and off? 

    Yes No
    INSTALL a new CCRM. Key in OFF position
    GO to  X7.
  7. X7 CHECK THE HFC CIRCUIT FOR AN OPEN IN THE HARNESS 
    • PCM connector disconnected.
    • Measure the resistance between:
    ( + ) PCM Connector, Harness Side ( - ) CCRM Connector, Harness Side
    HFC HFC

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  X8. REPAIR the open circuit.
  8. X8 CHECK THE HFC CIRCUIT FOR A SHORT TO POWER IN THE HARNESS 
    • Key in ON position.
    • Measure the voltage between:
    ( + ) CCRM Connector, Harness Side ( - )
    HFC Ground

    Is the voltage less than 1 V? 

    Yes No
    Key in OFF position
    GO to  X9.    		 REPAIR the short circuit.
  9. X9 CHECK THE HFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS 
    • Measure the resistance between:
    ( + ) CCRM Connector, Harness Side ( - )
    HFC Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  X10. REPAIR the short circuit.
  10. X10 COMMAND THE HIGH SPEED FAN ON 
    • PCM connector connected.
    • CCRM connector connected.
    • Key in ON position.
    • Enter Output Test Mode. Refer to OUTPUT TEST MODE .
    • Command the high speed fan ON.
    • Wait 10 seconds.
    • Command the outputs OFF.

    Did the High speed cooling fan turn on and off as expected? 

    Yes No
    Disregard DTC P1479/P0481 at this time
    Concern is elsewhere. RETURN to SYMPTOM CHARTS - CNG, FLEX-FUEL & GASOLINE for further direction.    		 INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM .
  11. X11 DTCS P1474 OR P0480: DOES THE FAN RUN WITH THE KEY IN THE ON POSITION? 

    Does the cooling fan always run with the key in the ON position? 

    Yes No
    Key in OFF position
    GO to  X14.    		 Key in OFF position
    GO to  X12.
  12. X12 CHECK THE FC/LFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS 
    • PCM connector disconnected.
    • CCRM connector disconnected.
    • Measure the resistance between:
    ( + ) CCRM Connector, Harness Side ( - )
    LFC Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  X13. REPAIR the short circuit.
  13. X13 CHECK THE FAN RUNNING MODE? 
    • CCRM connector connected.
    • Key in ON position.

    Is the fan running with the key on? 

    Yes No
    INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM . INSTALL a new CCRM.
  14. X14 CHECK THE FC/LFC CIRCUIT FOR AN OPEN IN THE HARNESS 
    • PCM connector disconnected.
    • CCRM connector disconnected.
    • Measure the resistance between:
    ( + ) PCM Connector, Harness Side ( - ) CCRM Connector, Harness Side
    LFC LFC

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  X15. REPAIR the open circuit.
  15. X15 CHECK THE FC/LFC CIRCUIT FOR A SHORT TO POWER IN THE HARNESS 
    • Key in ON position.
    • Measure the voltage between:
    ( + ) CCRM Connector, Harness Side ( - )
    LFC Ground

    Is the voltage less than 1 V? 

    Yes No
    Key in OFF position
    GO to  X16.    		 REPAIR the short circuit.
  16. X16 FC/LFC CIRCUIT FAULT ISOLATION CHECK 
    • CCRM connector disconnected.
    • Connect a 5 amp fused jumper wire between the following:
    Point A PCM Connector, Harness Side Point B
    LFC Ground
    • Key in ON position.

    Does the fan continue to run? 

    Yes No
    Key in OFF position. INSTALL a new PCM.
    Key in OFF position. INSTALL a new CCRM. Refer to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM .
  17. X17 CONTINUOUS MEMORY DTCS P1474 OR P0480: CHECK THE FC/LFC FOR AN OPEN OR SHORT CIRCUIT TO POWER 
    • CF Motor connector disconnected.
    • Connect a non-powered test lamp between:
    ( + ) CF Motor Connector, Harness Side ( - ) CF Motor Connector, Harness Side
    FAN PWR GND
    • Key in ON position.
    • Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns ON when a fault is detected.
      • Shake, wiggle, and bend the FC/LFC circuit between the PCM and CCRM.
      • Lightly tap on the CCRM to simulate road shock.

    Is a fault indicated? 

    Yes No
    Key in OFF position
    ISOLATE the fault and REPAIR as necessary.    		 GO to  X18.
  18. X18 CHECK THE FC/LFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS 
    • Key in ON position.
    • Enter Output Test Mode. Refer to OUTPUT TEST MODE .
    • Command the low speed fan ON.
    • Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns OFF when a fault is detected.
    • Shake, wiggle, and bend the FC/LFC circuit between the PCM and CCRM.
    • Lightly tap on the CCRM to simulate road shock.

    Is a fault indicated? 

    Yes No
    ISOLATE the fault and REPAIR as necessary. Key in OFF position
    GO to  Z1.
  19. X19 DTCS P1479 OR P0481: CHECK THE HFC FOR AN OPEN OR SHORT CIRCUIT TO POWER 
    NOTE: For one-speed fan applications, disregard DTC P1479/P0481.
    • CF Motor connector disconnected.
    • Inspect connectors for signs of damage, water ingress, corrosion, etc.
    • Connect a non-powered test lamp between:
    ( + ) CF Motor Connector, Harness Side ( - ) CF Motor Connector, Harness Side
    HFPWR GND
    • Key in ON position.
    • Enter Output Test Mode. Refer to OUTPUT TEST MODE .
    • Command the high speed fan ON.
    • Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns OFF when a fault is detected.
    • Shake, wiggle, and bend the HFC circuit between the PCM and CCRM.
    • Lightly tap on the CCRM to simulate road shock.

    Is a fault indicated? 

    Yes No
    Key in OFF position
    ISOLATE the fault and REPAIR as necessary.    		 GO to  X20.
  20. X20 CHECK THE HFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS 
    • Key in ON position.
    • Enter Output Test Mode. Refer to OUTPUT TEST MODE .
    • Command the outputs OFF.
    • Observe the test lamp for an indication of a fault while completing the following. Note that the lamp turns ON when a fault is detected.
    • Shake, wiggle, and bend the HFC circuit between the PCM and CCRM.
    • Lightly tap on the CCRM to simulate road shock.

    Is a fault indicated? 

    Yes No
    ISOLATE the fault and REPAIR as necessary
    RESTORE vehicle.    		 Key in OFF position
    GO to  Z1.
  21. X21 ELECTRIC COOLING FAN FUNCTIONAL CHECK 
    NOTE: For the proper results of these pinpoint tests, no DTCs must have been present during PCM Quick Test.
    • Key in ON position.
    • Enter Output Test Mode. Refer to OUTPUT TEST MODE .
    • Command the low speed fan ON.
    • For 2 speed fan applications, check both fan speeds.
    • Command the outputs OFF.

    Does the fan(s) operate at all speeds? 

    Yes No
    Key in OFF position
    Concern is elsewhere. RETURN to SYMPTOM CHARTS - CNG, FLEX-FUEL & GASOLINE for further direction.    		 For 3.8L
    GO to  X23
    For 3.9L
    GO to  X23
    For 4.6L
    GO to  X22.
  22. X22 ELECTRIC COOLING FAN CONCERN: DID THE FAN OPERATE AT ANY SPEED? 

    During the operational check of both speeds, did the fan(s) operate at any speed? 

    Yes No
    Only 1 FAN is operational
    GO to  X28.    		 FAN will not operate at any speed
    GO to  X23.
  23. X23 COOLING FAN WILL NOT OPERATE AT ANY SPEED: COMMAND FAN ON AND CHECK FOR VOLTAGE AT FAN 
    • Key in ON position.
    • CF Motor connector disconnected.
    • Command the low speed fan ON.
    • Measure the voltage between:
    ( + ) CF Motor Connector, Harness Side ( - )
    FAN PWR Ground

    Is the voltage greater than 10 V? 

    Yes No
    Key in OFF position
    GO to  X27.    		 Key in OFF position
    GO to  X24.
  24. X24 CHECK FOR B+ TO FAN CONTROL RELAYS IN CCRM 
    • CCRM connector disconnected.
    • Measure the voltage between:
    ( + ) CCRM Connector, Harness Side ( - )
    B+ (A) Ground

    Is the voltage greater than 10 V? 

    Yes No
    For 3.8L
    GO to  X26
    For 3.9L
    GO to  X26
    For 4.6L
    GO to  X25.    		 B+ circuit fault. CHECK the condition of the related fuse/fuse links. If OK, REPAIR the open circuit. If the fuse/fuse link is damaged, CHECK the circuit for short to ground before replacing.
  25. X25 CHECK FOR AN OPEN FAN POWER CIRCUIT BETWEEN THE CCRM AND COOLING FAN 
    • Measure the resistance between:
    ( + ) CF Motor Connector, Harness Side ( - ) CCRM Connector, Harness Side
    HFPWR HFPWR
    LFPWR LFPWR

    Are the resistances less than 5 ohms? 

    Yes No
    INSTALL a new CCRM
    Verify the applicable FAN PWR circuit is not shorted to ground    		 REPAIR the open circuit.
  26. X26 CHECK FOR AN OPEN FAN POWER CIRCUIT BETWEEN THE CCRM AND COOLING FAN 
    • Measure the resistance between:
    ( + ) CCRM Connector, Harness Side ( - ) CF Motor Connector, Harness Side
    FAN PWR FAN PWR

    Is the resistance less than 5 ohms? 

    Yes No
    INSTALL a new CCRM
    Verify the applicable FAN PWR circuit is not shorted to ground    		 REPAIR the open circuit.
  27. X27 CHECK FOR AN OPEN CF GROUND CIRCUIT(S) 
    • Measure the resistance between:
    ( + ) CF Motor Connector, Harness Side ( - )
    GND Ground

    Is the resistance less than 5 ohms? 

    Yes No
    INSTALL a new CF motor. REPAIR the open circuit.
  28. X28 DETERMINE WHICH FAN SPEED IS OPERATIONAL 

    Was the low speed fan operational? 

    Yes No
    GO to  X32. GO to  X29.
  29. X29 LOW SPEED FAN INOPERATIVE: COMMAND THE LOW SPEED FAN ON AND CHECK FOR VOLTAGE TO THE COOLING FAN 
    • Key in ON position.
    • CF Motor connector disconnected.
    • Enter Output Test Mode. Refer to OUTPUT TEST MODE .
    • Command the low speed fan ON.
    • Measure the voltage between:
    ( + ) CF Motor Connector, Harness Side ( - )
    LFPWR Ground

    Is the voltage greater than 10 V? 

    Yes No
    Key in OFF position
    GO to  X31.    		 Key in OFF position
    GO to  X30.
  30. X30 CHECK THE LFPWR CIRCUIT FOR AN OPEN IN THE HARNESS 
    • CCRM connector disconnected.
    • Measure the resistance between:
    ( + ) CF Motor Connector, Harness Side ( - ) CCRM Connector, Harness Side
    LFPWR LFPWR

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  X34. REPAIR the open circuit.
  31. X31 CHECK FOR AN OPEN DROPPING RESISTOR ON THE FAN SHROUD ASSEMBLY 
    • Measure the resistance between:
    ( + ) CF Motor Connector, Component Side ( - ) CF Motor Connector, Component Side
    HFPWR LFPWR

    Is the resistance less than 6 ohms? 

    Yes No
    INSTALL a new CF motor. Verify the condition of the dropping resistor, and replace as necessary. If OK, replace the fan assembly.
  32. X32 HIGH SPEED FAN INOPERATIVE: COMMAND THE HIGH SPEED FAN ON AND CHECK FOR VOLTAGE TO THE COOLING FAN 
    • Key in ON position.
    • CF Motor connector disconnected.
    • Enter Output Test Mode. Refer to OUTPUT TEST MODE .
    • Command the high speed fan ON.
    • Measure the voltage between:
    ( + ) CF Motor Connector, Harness Side ( - ) Vehicle Battery
    HFPWR Negative terminal

    Is the voltage greater than 10.5 V? 

    Yes No
    INSTALL a new CF motor. Key in OFF position
    GO to  X33.
  33. X33 CHECK THE HFPWR CIRCUIT FOR AN OPEN IN THE HARNESS 
    • CCRM connector disconnected.
    • Measure the resistance between:
    ( + ) CF Motor Connector, Harness Side ( - ) CCRM Connector, Harness Side
    HFPWR HFPWR

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  X34. REPAIR the open circuit.
  34. X34 IS THE DIAGNOSTIC TOOL CAPABLE OF VIEWING PIDS WHILE IN OUTPUT TEST MODE? 
    NOTE: The symptom "low speed fan or high speed fan inoperative" can be caused by a primary circuit fault, even though a DTC was not set.

    Is the diagnostic tool capable of viewing PIDs while in output test mode? 

    Yes No
    GO to  X35. For low speed fan inoperative (fan inoperative for single speed fan): GO to  X36
    For high speed fan inoperative:
    GO to  X4.
  35. X35 CHECK THE OPERATION OF THE LOW SPEED FAN OR HIGH SPEED FAN PRIMARY CIRCUITS 
    • CCRM connector connected.
    • CF Motor connector connected.
    • Key in ON position.
    • Enter Output Test Mode. Refer to OUTPUT TEST MODE .
    • Command the outputs OFF.
    • Access the PCM and monitor the LFC and LFCF PIDs.
    • For low speed fan inoperative (fan inoperative for single speed fan applications):
    • With the LFC PID off (low speed fan commanded off by the PCM), the LFCF PID must indicate no fault (or NO).
    • Command the Low Speed Fan ON.
    • The LFC PID will be ON (the LFCF PID must still indicate no fault (or NO).
    • Enter Output Test Mode. Refer to OUTPUT TEST MODE .
    • Command the outputs OFF.
    • Access the PCM and monitor the HFC and HFCF PIDs.
    • With the HFC PID off (high speed fan commanded off by the PCM), the HFCF PID must indicate no fault (or NO).
    • Command the High Speed Fan ON.
    • The HFC PID will now be ON (the HFCF PID must still indicate no fault (or NO).

    Does the LFCF/HFCF PID indicate a fault (or YES)? 

    Yes No
    Key in OFF position
    An HFC or LFC primary circuit fault is detected
    For the LFCF PID indicating a fault:
    GO to  X11
    For the HFCF PID indicating a fault:
    GO to  X4.    		 INSTALL a new CCRM
    Verify the applicable FAN PWR circuit is not shorted to ground
  36. X36 CHECK THE FC/LFC CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS 
    • Diagnostic tool connector disconnected.
    • PCM connector disconnected.
    • Measure the resistance between:
    ( + ) CCRM Connector, Harness Side ( - )
    LFC Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    INSTALL a new CCRM
    Verify the applicable FAN PWR circuit is not shorted to ground    		 REPAIR the short circuit.
  37. X37 LOW AND/OR HIGH SPEED COOLING FAN ALWAYS RUNS (NO DTCS): VERIFY THE FAN IS NOT ON BECAUSE OF AC HIGH PRESSURE SWITCH INPUT TO THE PCM 
    • Key on engine running.
    • Access the PCM and monitor the ACP PID.

    Is the PID state CLOSED? 

    Yes No
    GO to  X38. GO to  X39.
  38. X38 CHECK THE ACHP SWITCH FUNCTION 
    • A/CHPSW connector disconnected.
    • Access the PCM and monitor the ACP PID.

    Is the PID state CLOSED? 

    Yes No
    Key in OFF position
    GO to  X68.    		 Key in OFF position
    Reconnect AC High Pressure Switch
    REFER to the appropriate CLIMATE CONTROL SYSTEM article to the diagnose symptom.
  39. X39 DISCONNECT THE CCRM AND CHECK IF THE FAN STILL RUNS 
    • Turn off all the accessories.
    • Key in ON position.
    • Verify the cooling fan always on symptom.
    • Key in OFF position.
    • CCRM connector disconnected.
    • Key in ON position.

    Is the cooling fan still on? 

    Yes No
    Key in OFF position
    For 3.8/3.9L Mustang: REPAIR the short to power in the FAN PWR circuit
    For all others: GO to  X40.    		 Key in OFF position
    GO to  X41.
  40. X40 CHECK THE LFPWR & HFPWR CIRCUIT FOR A SHORT TO POWER IN THE HARNESS 
    • CF Motor connector disconnected.
    • Key in ON position.
    • Measure the voltage between:
    ( + ) CF Motor Connector, Harness Side ( - )
    HFPWR Ground
    LFPWR Ground

    Are the voltages less than 1 V? 

    Yes No
    Key in OFF position
    Concern is elsewhere. RETURN to SYMPTOM CHARTS - CNG, FLEX-FUEL & GASOLINE for further direction.    		 REPAIR the short circuit.
  41. X41 CHECK THE OPERATION OF THE LOW SPEED FAN OR HIGH SPEED FAN PRIMARY CIRCUITS 
    NOTE: The symptom "cooling fan always runs" can be caused by a primary circuit fault, even though a DTC was not set. This step checks the primary circuit operation.
    • CCRM connector connected.
    • Key in ON position.
    • Access the PCM and monitor the LFC and LFCF PIDs.
    • With the LFC PID off (low speed fan commanded off by the PCM), the LFCF PID must indicate no fault (or NO).
    • Access the PCM and monitor the HFC and HFCF PIDs.
    • For all except 3.8/3.9L Mustang:
      • With the HFC PID off (high speed fan commanded off by the PCM), the HFCF PID must indicate no fault (or NO).

    Does the HFCF/LFCF PID indicate a fault (or YES)? 

    Yes No
    Key in OFF position
    An HFC or LFC primary circuit fault is detected
    For the LFCF PID indicating a fault:
    GO to  X11.
    For the HFCF PID indicating a fault:
    GO to  X4.    		 INSTALL a new CCRM.
  42. X42 LACK OF COOLING/AC NOT FUNCTIONING: CHECK FOR VOLTAGE TO AC CLUTCH 
    • Key in OFF position.
    • A/CCS Switch connector disconnected.
    • Connect a 5 amp fused jumper wire between the following:
      Point A A/CCS Switch Connector, Harness Side Point B A/CCS Switch Connector, Harness Side
      A/CDSW A/CCS
    • A/CC Assembly connector disconnected.
    • Measure the voltage between:
    ( + ) A/CC Assembly Connector, Harness Side ( - ) A/CC Assembly Connector, Harness Side
    A/CC PWR GND
    • Key on engine running.
    • Turn On AC Switch. Wait for 15 seconds.
    • Measure the voltage between:
    ( + ) A/CC Assembly Connector, Harness Side ( - ) A/CC Assembly Connector, Harness Side
    A/CC PWR GND

    Is the voltage greater than 10.5 V? 

    Yes No
    Key in OFF position
    Remove the jumper wire(s)
    Reconnect A/CCS.
    3.8/3.9L and 4.6L not covered below:
    REFER to the appropriate CLIMATE CONTROL SYSTEM article to the diagnose symptom.
    For a 4.6L with the symptom "poor A/C system performance in hot ambient temperature":
    GO to  X71.    		 Key in OFF position
    GO to  X43.
  43. X43 CHECK THE ACCS INPUT TO THE PCM WITH THE AC ON 
    • A/CC Assembly connector connected.
    • Key on engine running.
    • Turn On AC Switch.
    • Access the PCM and monitor the ACCS PID.
    • After testing, remove the jumper, reconnect A/CCS and turn the key to the OFF position.

    Is the PID state ON? 

    Yes No
    Key in OFF position
    GO to  X55.    		 GO to  X44.
  44. X44 THE ACCS PID IS OFF WITH THE AC ON. CHECK FOR VOLTAGE TO THE AC_CYC SWITCH 
    • Remove the jumper wire(s)
    • Key in ON position.
    • A/CCS Switch connector disconnected.
    • AC demand switch to AC on.
    • Measure the voltage between:
    ( + ) A/CCS Switch Connector, Harness Side ( - )
    A/CDSW Ground

    Is the voltage greater than 10.5 V? 

    Yes No
    Key in OFF position
    GO to  X45.    		 Key in OFF position
    REFER to the appropriate CLIMATE CONTROL SYSTEM article to the diagnose symptom.
  45. X45 CHECK IF THE AC_CYC CONTACTS ARE CLOSED 
    • Measure the resistance between:
    ( + ) A/CCS Switch Connector, Component Side ( - ) A/CCS Switch Connector, Component Side
    A/CDSW A/CCS

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  X46. REFER to the appropriate CLIMATE CONTROL SYSTEM article to the diagnose symptom.
  46. X46 CHECK FOR VOLTAGE TO THE DUAL FUNCTION AC_CYC 
    • A/CCS Switch connector connected.
    • A/CHPSW connector disconnected.
    • Key in ON position.
    • Turn On AC Switch.
    • Measure the voltage between:
    ( + ) A/CHPSW Connector, Harness Side ( - )
    ACCS-A Ground

    Is the voltage greater than 10.5 V? 

    Yes No
    Key in OFF position
    GO to  X47.    		 REPAIR the open circuit.
  47. X47 CHECK THE RESISTANCE OF THE ACHP HIGH PRESSURE CONTACTS 
    • Measure the resistance between:
    ( + ) A/CHPSW Connector, Component Side ( - ) A/CHPSW Connector, Harness Side
    A/CPSW GND

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  X48. REFER to the appropriate CLIMATE CONTROL SYSTEM article to the diagnose symptom.
  48. X48 CHECK FOR VOLTAGE TO THE PCM ON THE ACCS CIRCUIT 
    • A/CHPSW connector connected.
    • PCM connector disconnected.
    • Key in ON position.
    • Turn On AC Switch.
    • Measure the voltage between:
    ( + ) PCM Connector, Harness Side ( - )
    A/CCS Ground

    Is the voltage greater than 10.5 V? 

    Yes No
    INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM . REPAIR the open circuit.
  49. X49 KOEO AND KOER DTCS P1460 OR P0645: VERIFY THAT ACCS PID IS OFF 
    NOTE: Verify the AC and defrost were off during the KOEO/KOER self-tests. If the vehicle is not equipped with AC, the WAC circuit is not used and DTC P1460/P0645 can be ignored.
    • key on engine running.
    • AC and defroster OFF.
    • Access the PCM and monitor the ACCS PID.

    Is the PID state OFF? 

    Yes No
    Key in OFF position
    GO to  X50.    		 Key in OFF position
    GO to  X61.
  50. X50 CHECK THE A/CCR (WAC) CIRCUIT IN THE CCRM 
    • CCRM connector disconnected.
    • Measure the resistance between:
    ( + ) CCRM Connector, Component Side ( - ) CCRM Connector, Component Side
    A/CCR VPWR

    Is the resistance between 130 ohms - 200 ohms? 

    Yes No
    GO to  X51. INSTALL a new CCRM
    Start Engine
    Turn On AC Switch
    Wait 15 seconds
    Turn Off AC Switch
    Rerun the Quick Test.
  51. X51 CHECK THE CCRM FOR INTERNAL SHORTS 
    • Measure the resistance between:
      ( + ) CCRM Connector, Harness Side ( - )
      HFC Ground
    • Measure the resistance between:
    ( + ) CCRM Connector, Harness Side ( - ) CCRM Connector, Harness Side
    HFC IGN START/RUN
    HFC CCRM Case
    HFC LFPWR
    HFC B+
    HFC FPDM PWR
    HFC HFPWR
    HFC GND

    Are the resistances greater than 1K ohms? 

    Yes No
    GO to  X52. INSTALL a new CCRM
    Start Engine
    Turn On AC Switch
    Wait 15 seconds
    Turn Off AC Switch
    Rerun the Quick Test.
  52. X52 CHECK THE A/CCR (WAC) CIRCUIT FOR A SHORT TO POWER IN THE HARNESS 
    • PCM connector disconnected.
    • Key in ON position.
    • Measure the voltage between:
    ( + ) CCRM Connector, Harness Side ( - )
    A/CCR Ground

    Is the voltage less than 1 V? 

    Yes No
    Key in OFF position
    GO to  X53.    		 REPAIR the short circuit
    Start Engine
    Turn On AC Switch
    Wait 15 seconds
    Turn Off AC Switch
    Rerun the Quick Test.
  53. X53 CHECK THE A/CCR (WAC) CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS 
    • Measure the resistance between:
    ( + ) CCRM Connector, Harness Side ( - )
    A/CCR Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  X54. REPAIR the short circuit
    Start Engine
    Turn On AC Switch
    Wait 15 seconds
    Turn Off AC Switch
    Rerun the Quick Test.
  54. X54 CHECK THE A/CCR (WAC) CIRCUIT FOR AN OPEN IN THE HARNESS 
    • Measure the resistance between:
    ( + ) PCM Connector, Harness Side ( - ) CCRM Connector, Harness Side
    A/CCR A/CCR

    Is the resistance less than 5 ohms? 

    Yes No
    INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM .
    Start Engine
    Turn On AC Switch
    Wait 15 seconds
    Turn Off AC Switch
    Rerun the Quick Test.    		 REPAIR the open circuit
    Start Engine
    Turn On AC Switch
    Wait 15 seconds
    Turn Off AC Switch
    Rerun the Quick Test.
  55. X55 NO/LOW VOLTAGE TO ACC: CHECK FOR VOLTAGE TO THE CCRM 
    • CCRM connector disconnected.
    • Key in ON position.
    • Measure the voltage between:
    ( + ) CCRM Connector, Harness Side ( - )
    B+ Ground

    Is the voltage greater than 10.5 V? 

    Yes No
    Key in OFF position
    GO to  X56.    		 There is a B+ or IGN START/RUN circuit fault. CHECK the condition of the related fuse(s)/diode. If OK, REPAIR the open circuit. If the fuse is damaged, check the IGN START/RUN or B+ and VPWR circuits for a short to ground before replacing.
  56. X56 CHECK FOR OPEN A/CC PWR AND A/CC GND CIRCUITS 
    • ACCS Assembly connector disconnected.
    • Measure the resistance between:
    ( + ) A/CC Assembly Connector, Harness Side ( - ) CCRM Connector, Harness Side
    A/CC PWR A/CC PWR
    GND A/CC GND

    Are the resistances less than 5 ohms? 

    Yes No
    INSTALL a new CCRM
    Verify the applicable A/CC PWR circuit is not shorted to ground    		 REPAIR the open circuit.
  57. X57 DTCS P1469 OR P0534: CHECK FOR THE CAUSES OF FAST ACCS CYCLING 
    • REFER to the appropriate CLIMATE CONTROL SYSTEM article to check the A/C system pressure, to test the ACCS cycle times, and to check the causes of fast ACCS cycling.

    Is a fault indicated? 

    Yes No
    REPAIR as required
    CLEAR the DTCs
    Start EngineTurn On AC Switch
    Wait 120 seconds
    Turn Off AC Switch
    Rerun the Quick Test.    		 GO to  X58.
  58. X58 CHECK FOR AN INTERMITTENT OPEN IN THE ACCS CIRCUIT 
    • Key in ON position.
    • Access the PCM and monitor the ACCS PID.
    • Turn On AC Switch.
    • Observe the ACCS PID for an indication of a fault while completing the following: (the ACCS PID turns off and on quickly when a fault is detected, indicating an intermittent open).
      • Shake, wiggle, and bend the ACCS circuit between the PCM and the source of the circuit.
      • Lightly tap on the PS to simulate road shock.
    • Disconnect and inspect the AC_CYC connector.

    Is a fault indicated? 

    Yes No
    Key in OFF position
    ISOLATE the fault and REPAIR as necessary
    CLEAR the DTCs
    Start Engine
    Turn On AC Switch
    Wait 120 seconds
    Turn Off AC Switch
    Rerun the Quick Test.    		 Unable to duplicate or identify the fault at this time
    CLEAR the DTCs and REPEAT the self-test
    Return to SYMPTOM CHARTS - CNG, FLEX-FUEL & GASOLINE to continue diagnosis.
  59. X59 CONTINUOUS MEMORY DTCS P1460 OR P0645: CHECK THE WAC CIRCUIT FOR AN INTERMITTENT OPEN OR SHORTS 
    NOTE: If the vehicle is not equipped with AC, the WAC circuit is not used and the P1460/P0645 can be ignored.
    • A/CCS Switch connector disconnected.
    • Connect a 5 amp fused jumper wire between the following:
      Point A A/CCS Switch Connector, Harness Side Point B A/CCS Switch Connector, Harness Side
      A/CDSW A/CCS
    • Key in ON position.
    • Turn On ACD Switch.
    • CHECK the A/CCR (WAC) circuit for an open or short to power while completing the following:
      • The A/CC clicks on when a fault is detected.
      • Shake, wiggle, and bend the A/CCR (WAC) circuit(s).
      • Lightly tap on the CCRM to simulate road shock.
    • Enter Output Test Mode. Refer to OUTPUT TEST MODE .
    • Command the outputs OFF.
    • CHECK the WAC circuit for a short to ground while performing the following:
      • The WAC clicks off when a fault is detected.
      • Shake, wiggle, and bend the WAC circuit(s).
      • Lightly tap on the CCRM to simulate road shock.
    • Key in OFF position.
    • Turn Off AC Switch.

    Is a fault indicated? 

    Yes No
    ISOLATE the fault and REPAIR as necessary
    CLEAR the DTCs
    Start Engine
    Turn On AC Switch
    Wait 15 seconds
    Turn Off AC Switch
    Rerun the Quick Test.    		 Remove the jumper wire(s)
    GO to  Z1.
  60. X60 DTC P1464: CHECK THE ACCS PID 
    NOTE: Verify the AC and defrost were off during the self-test. If AC or defrost was on, turn off and rerun the self-test.
    • Key in ON position.
    • AC and defroster OFF.
    • Access the PCM and monitor the ACCS PID.

    Is the ACCS PID on? 

    Yes No
    Key in OFF position
    GO to  X61.    		 The ACCS PID indicates that the ACCS input to the PCM is low
    Verify the test step results
    AC and defroster OFF
    Rerun the self-test where the DTC P1464 was received.
  61. X61 ACCS PID ON: DISCONNECT THE A/CCS AND CHECK IF THE ACCS PID TURNS OFF 
    • A/CCS Switch connector disconnected.
    • Key in ON position.
    • Access the PCM and monitor the ACCS PID.

    Is the ACCS PID off? 

    Yes No
    Key in OFF position
    Verify operation of the A/CDSW
    If OK, REPAIR the short to power in the A/CCS circuit    		 Key in OFF position
    GO to  X62.
  62. X62 CHECK THE A/CC PWR CIRCUIT FOR A SHORT TO POWER IN THE HARNESS 
    • CCRM connector disconnected.
    • Key in ON position.
    • Measure the voltage between:
    ( + ) CCRM Connector, Harness Side ( - )
    A/CC PWR Ground

    Is the voltage less than 1 V? 

    Yes No
    GO to  X63. REPAIR the short circuit.
  63. X63 CHECK THE ACCS CIRCUIT FOR A SHORT TO POWER IN THE HARNESS 
    • Key in OFF position.
    • PCM connector disconnected.
    • Key in ON position.
    • Measure the voltage between:
    ( + ) PCM Connector, Harness Side ( - )
    A/CCS Ground

    Is the voltage less than 1 V? 

    Yes No
    Key in OFF position
    GO to  X64.    		 REPAIR the short circuit.
  64. X64 CHECK THE ACCS CIRCUIT VOLTAGE TO THE PCM WITH THE CCRM CONNECTED 
    • CCRM connector connected.
    • Key in ON position.
    • Measure the voltage between:
    ( + ) PCM Connector, Harness Side ( - )
    A/CCS Ground

    Is the voltage less than 1 V? 

    Yes No
    INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM . INSTALL a new CCRM.
  65. X65 DOES THE AC TURN OFF WHEN THE AC_SW IS TURNED OFF? 

    Does the AC turn off when the AC_SW is turned off? 

    Yes No
    GO to  X66 GO to  X69.
  66. X66 CHECK IF THE AC CUTS OFF DURING WOT 
    • Key on engine running.
    • Turn On AC Switch.
    • Initiate brief WOT and return to idle. Listen for the ACCS to disengage during WOT, then re-engage a few seconds after returning to idle. A "click" sound can be heard when the clutch re-engages.
      NOTE: If the clicking sound cannot be heard, disconnect to ACCS. With a test lamp connected between the power pin and ground pin of the ACCS, observe the test lamp while performing the brief WOT. The test lamp must go off during the brief WOT, then come back on a few seconds after returning to idle.
    • Repeat the test, if necessary, to verify the results.

    Does the ACCS or test lamp operate as indicated? 

    Yes No
    Key in OFF position
    Reconnect A/CC
    GO to  Z1.    		 GO to  X67.
  67. X67 NO WOT AC CUTOFF, NO DTCS PRESENT: CHECK THE CCRM 
    • A/CC Assembly connector connected.
    • Key in ON position.
    • Enter Output Test Mode. Refer to OUTPUT TEST MODE .
    • Command the outputs ON.
    • Turn On A/CDSW Switch.
    • While listening to the ACCS, command the outputs off and on several times.

    Does the ACCS engage and disengage when the outputs are cycled on and off? 

    Yes No
    Key in OFF position
    If the symptom is intermittent, GO to  Z1.
    Otherwise, return to SYMPTOM CHARTS - CNG, FLEX-FUEL & GASOLINE to repair any additional symptoms.    		 INSTALL a new CCRM.
  68. X68 CHECK THE ACPSW CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS 
    • A/CHPSW connector disconnected.
    • PCM connector disconnected.
    • Measure the resistance between:
    ( + ) PCM Connector, Harness Side ( - )
    A/CLPCS Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM . REPAIR the short circuit.
  69. X69 AC IS ALWAYS ON: CHECK FOR VOLTAGE AT THE A/C CLUTCH WITH THE A/C OFF 
    • AC and defroster OFF.
    • A/CC Assembly connector disconnected.
    • Measure the voltage between:
    ( + ) A/CC Assembly Connector, Harness Side ( - ) A/CC Assembly Connector, Harness Side
    A/CC PWR GND
    • Key on engine running.
    • Monitor the voltage.
    • Measure the voltage between:
    ( + ) A/CC Assembly Connector, Harness Side ( - ) A/CC Assembly Connector, Harness Side
    A/CC PWR GND

    Is the voltage less than 2 V? 

    Yes No
    REFER to the appropriate CLIMATE CONTROL SYSTEM article to the diagnose symptom. GO to  X70.
  70. X70 CHECK THE ACCS INPUT TO THE PCM WITH THE AC OFF 
    • Key in OFF position.
    • Connect the diagnostic tool to data link connector (DLC).
    • Key on engine running.
    • AC and defroster OFF.
    • Access the PCM and monitor the ACCS PID.

    Is the PID state OFF? 

    Yes No
    Key in OFF position
    REFER to the appropriate CLIMATE CONTROL SYSTEM article to the diagnose symptom.    		 GO to  X61.
  71. X71 CHECK THE ACHP MEDIUM PRESSURE CIRCUITS 
    NOTE: An A/CHPSW medium pressure circuit concern can result in the high speed cooling fan not coming on when A/C refrigerant pressure becomes high. In hot ambient conditions, this may result in the refrigerant pressure continuing to increase until the A/C high pressure switch contacts open, shutting off the A/C until the pressure drops to an acceptable range.
    • Key in OFF position.
    • A/CHPSW connector disconnected.
    • Turn the AC off.
    • Connect a 5 amp fused jumper wire between the following:
    Point A A/CHPSW Connector, Harness Side Point B A/CHPSW Connector, Harness Side
    A/CPSW GND
    • Key on engine running.
    • Wait 15 seconds.

    Does the High speed cooling fan come on? 

    Yes No
    Key in OFF position
    Remove the jumper wire(s) Reconnect Air Conditioning High Pressure Switch
    REFER to the appropriate CLIMATE CONTROL SYSTEM article to the diagnose symptom.    		 GO to  X72.
  72. X72 CHECK FOR AN OPEN AIR CONDITIONING HIGH PRESSURE SWITCH GROUND CIRCUIT(S) 
    • Key on engine running.
    • Connect a 5 amp fused jumper wire between the following:
    Point A A/CHPSW Connector, Harness Side Point B Vehicle Battery
    A/CLPCS Negative terminal
    • Wait for 15 seconds.

    Does the High speed cooling fan come on? 

    Yes No
    Key in OFF position. REPAIR the open circuit
    Remove the jumper wire(s)    		 Key in OFF position
    Remove the jumper wire(s) GO to  X73.
  73. X73 CHECK FOR AN OPEN CIRCUIT BETWEEN PCM & A/CHPSW 
    • PCM connector disconnected.
    • Measure the resistance between:
    ( + ) PCM Connector, Harness Side ( - ) A/CHPSW Connector, Harness Side
    ACPSW A/CPSW

    Is the resistance less than 5 ohms? 

    Yes No
    INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM . REPAIR the open circuit.
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