Pinpoint Test J : The A/C (Air Conditioning) Is Always On -- A/C (Air Conditioning) Mode Always Commanded On
- Refer to Manual Climate Control System
for schematic and connector information.
Normal Operation and Fault Conditions
A/C Request, REFER to: Climate Control System - Vehicles With: Electronic Manual Temperature Control (EMTC) - System Operation and Component Description .
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition PCM P1464:00 A/C Demand Out Of Self Test Range: No Sub Type Information PCM senses an A/C request during a self-test. Possible Sources
- Wiring, terminals or connectors
- A/C pressure transducer
- Evaporator temperature sensor
- HVAC control module
- PCM
Visual Inspection and Pre-checks
- Inspect for loose or corroded PCM or HVAC control module connections.
- J1 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 J2 No IGNORE the DTC and CONTINUE diagnosing other Diagnostic Trouble Codes (DTCs) or symptoms. GO to PCM DTC Chart or Symptom Chart - Climate Control Systems . - J2 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.
- Ignition ON.
- Measure:
Positive Lead Measurement / Action Negative Lead C100-1 Ground
Is any voltage present?
Yes REPAIR the circuit. No GO to J3 - J3 COMPARE THE HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE 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 the outside ambient temperature.
- Ignition ON.
- Using a diagnostic scan tool, view the PCM Parameter Identification (PIDs).
- Monitor and record the PCMPID AAT.
- Using a diagnostic scan tool, view the HVAC control module Parameter Identification (PIDs).
- Monitor and record the HVAC control module PID EVAP_TEMP.
Are the temperature values similar (typically within 18 deg.C (32.4 deg.F))?
Yes GO to J4 No GO to Pinpoint Test D - J4 CHECK THE A/C (AIR CONDITIONING) PRESSURE SENSOR (ACP_PRESS) PARAMETER IDENTIFICATION (PID)
- Ignition ON.
- 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 PCMPID within +/- 103 kPa (15 psi)?
Yes GO to J5 No GO to Pinpoint Test B - J5 CHECK THE HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE A/C (AIR CONDITIONING) SWITCH STATUS (CC_SW_AC) PID (PARAMETER IDENTIFICATION) WITH THE A/C (AIR CONDITIONING) OFF
- Ignition ON.
- Using a diagnostic scan tool, monitor the HVAC control module CC_SW_AC PID.
- Using the HVAC controls, select PANEL then press and release the A/C button (indicator off).
Does the PID display On when the A/C button is pressed and Off when released?
Yes GO to J6 No GO to J8 - J6 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, monitor the PCM AC_REQ PID.
- Using the HVAC controls, deactivate the A/C.
Does the PID display OFF?
Yes GO to J8 No GO to J7 - J7 CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) REQUEST SIGNAL (AC_REQ) PID (PARAMETER IDENTIFICATION) WITH THE HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE DISCONNECTED
- Ignition OFF.
- Disconnect HVAC control module C228A.
- Ignition ON.
- Using a diagnostic scan tool, monitor the PCM AC_REQ PID.
Does the PID display OFF?
Yes GO to J8 No GO to J9 - J8 CHECK FOR CORRECT HVAC (HEATING, VENTILATION AND AIR CONDITIONING) CONTROL MODULE OPERATION
- Ignition OFF.
- Disconnect and inspect all HVAC control module electrical connectors (if not previously disconnected).
- Repair:
- corrosion (install new connector or terminal - clean module pins)
- damaged or bent pins - install new terminals or pins
- pushed-out pins - install new pins as necessary
- Connect all HVAC control module electrical 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 service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new HVAC control module. REFER to the appropriate procedure in Climate Control System . 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. - J9 CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION
- Ignition OFF.
- Disconnect and inspect all PCM electrical connectors (if not previously disconnected).
- Repair:
- corrosion (install new connector or terminal - clean module pins)
- damaged or bent pins - install new terminals or pins
- pushed-out pins - install new pins as necessary
- Connect all PCM electrical 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 service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, Refer to PCM Guided Routine Testing . 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.