Pinpoint Test H : The A/C (Air Conditioning) Is Always On - A/C (Air Conditioning) Mode Always Commanded On
- H1 RECHECK THE PCM (POWERTRAIN CONTROL MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)
- Ignition ON.
- Make sure the HVAC control module is powered off.
- Using a diagnostic scan tool, clear the PCM Diagnostic Trouble Codes (DTCs).
- Using a diagnostic scan tool, carry out the PCM KOEO self-test.
Does DTC P1464 return?
Yes GO to H2 No IGNORE the DTC and CONTINUE diagnosing other Diagnostic Trouble Codes (DTCs) or symptoms. GO to DTC Chart: Powertrain Control Module (PCM) or Symptom Chart: Climate Control - Electronic Manual Temperature Control (EMTC) . - H2 CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY
- Carry out the component test on the A/C clutch relay. Refer to Carry out the component test on the A/C clutch relay. Refer to Component Testing for schematic and connector information.
Did the relay pass the component test?
Yes GO to H3 No INSTALL a new A/C clutch relay. - H3 CHECK THE A/C (AIR CONDITIONING) COMPRESSOR CLUTCH FIELD COIL VOLTAGE SUPPLY CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect A/C compressor clutch field coil C100 .
- Disconnect the A/C clutch relay.
- Ignition ON.
- Measure:
Positive Lead Measurement / Action Negative Lead C100-1 Ground
Is any voltage present?
Yes REPAIR the circuit. No GO to H4 - H4 COMPARE THE FCIM (FRONT CONTROLS INTERFACE MODULE) A/C EVAPORATOR TEMPERATURE (EVAP_TEMP) PID (PARAMETER IDENTIFICATION) TO THE PCM (POWERTRAIN CONTROL MODULE) AMBIENT AIR TEMPERATURE (AAT) PID (PARAMETER IDENTIFICATION)
- Ignition OFF.
- Allow the vehicle exterior and interior to stabilize to ambient temperature.
- Ignition ON.
- Using a diagnostic scan tool, view the PCM Parameter Identification (PIDs).
- Monitor and record the PCM PID AAT.
- Using a diagnostic scan tool, view the FCIM Parameter Identification (PIDs).
- Monitor and record the FCIM PID EVAP_TEMP.
Are the temperature values similar (typically within 18 °C (32.4 °F))?
Yes GO to H5 No GO to Pinpoint Test L - H5 CHECK THE FCIM (FRONT CONTROLS INTERFACE MODULE) A/C (AIR CONDITIONING) SWITCH STATUS (CC_SW_AC) PID (PARAMETER IDENTIFICATION)
- Ignition ON.
- Using a diagnostic scan tool, view FCIM Parameter Identifications (PIDs).
- Monitor the CC_SW_AC PID.
- Select panel mode, press and release the A/C button (indicator off) on the FCIM controls.
Does the PID display Active when pressed and Inactive when released?
Yes GO to H6 No GO to H9 - H6 CHECK THE A/C (AIR CONDITIONING) PRESSURE SENSOR (ACP_PRESS) PARAMETER IDENTIFICATION (PID)
- Using a diagnostic scan tool, view the PCM Parameter Identification (PIDs).
- With a manifold gauge set connected, compare the pressure readings of the manifold gauge set and the PCM Parameter Identification (PID) ACP_PRESS.
Are the pressure values of the manifold gauge set and the ACP_PRESS PCM PID within ± 103 kPa (15 psi)?
Yes GO to H7 No DIAGNOSE the A/C pressure transducer. GO to Pinpoint Test A - H7 CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) REQUEST SIGNAL (AC_REQ) PID (PARAMETER IDENTIFICATION) WITH THE A/C (AIR CONDITIONING) OFF
- Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
- Monitor the AC_REQ PID.
- While in panel mode, release the A/C button (indicator off) on the HVAC controls.
Does the PID display No or OFF?
Yes GO to H10 No GO to H8 - H8 CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) REQUEST SIGNAL (AC_REQ) PID (PARAMETER IDENTIFICATION) WITH FCIM (FRONT CONTROLS INTERFACE MODULE) DISCONNECTED
- Ignition OFF.
- Disconnect FCIM C2402A .
- Ignition ON.
- Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
- Monitor the AC_REQ PID.
Does the PID display No or OFF?
Yes GO to H10 No GO to H9 - H9 CHECK FOR CORRECT FCIM (FRONT CONTROLS INTERFACE MODULE) OPERATION
- Ignition OFF.
- Disconnect and inspect all FCIM connectors.
- Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary
- Reconnect all FCIM connectors. Make sure they seat and latch correctly.
- Operate the system and determine if the concern is still present.
Is the concern still present?
Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, Refer to FCIM HARDWARE TESTING . No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues. - H10 CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION
- Ignition OFF.
- Disconnect and inspect all PCM connectors.
- Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary
- Reconnect all PCM connectors. Make sure they seat and latch correctly.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new PCM. Refer to: Powertrain Control Module (PCM) - 6.2L V8 . Refer to: Powertrain Control Module (PCM) - 6.8L Triton-30V - V10 . Refer to: Powertrain Control Module (PCM) - 6.7L Power Stroke Diesel . No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.