Pinpoint Test B: P0645:00, P2CFC:00, P2CFD:00, P2CFE:00, P2CFF:00
- Refer to MANUAL CLIMATE CONTROL SYSTEM
for schematic and connector information.
Normal Operation and Fault Conditions
When A/C is requested and A/C conditions allow, the PCM grounds the clutch control circuit that is hardwired to the A/C clutch control input processing in the BCM. For additional information on 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 P0645:00 A/C Clutch Relay Control Circuit: No Sub Type Information Sets when the PCM grounds the relay control circuit and erratic current is detected on the relay control circuit. The DTC also sets when the relay control circuit is off and voltage is detected on the relay circuit. PCM P2CFC:00 A/C Clutch Control Circuit: No Sub Type Information Sets when the PCM grounds the relay control circuit and more current than expected is detected on the relay control circuit. PCM P2CFD:00 A/C Clutch Control Circuit Low: No Sub Type Information Sets when the PCM grounds the relay control circuit and less current than expected is detected on the relay control circuit. PCM P2CFE:00 A/C Clutch Control Circuit High: No Sub Type Information Sets when the PCM grounds the relay control circuit and excessive current is detected on the relay control circuit. PCM P2CFF:00 A/C Clutch Control Circuit Driver Current/Temperature Too High: No Sub Type Information Sets when the PCM grounds the relay control circuit and more current and temperature than expected is detected on the relay control circuit. Possible Sources
- Fuse
- Wiring, terminals or connectors
- A/C clutch relay [non-serviceable, part of the BJB]
- PCM
- NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector.
- B1 CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY COIL CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect PCM C175B (2. 3L) or C1551B (2. 7L).
- Disconnect BJB C1035A.
- Ignition ON.
- Measure:
Positive Lead Measurement / Action Negative Lead C1035A-20 Ground
Is any voltage present?
Yes REPAIR the circuit. No GO to B2 - B2 CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY COIL CONTROL CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Measure:
Positive Lead Measurement / Action Negative Lead C1035A-20 Ground
Is the resistance greater than 10, 000 ohms?
Yes GO to B3 No REPAIR the circuit. - B3 CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY COIL CONTROL CIRCUIT FOR AN OPEN
- Measure:
2. 3L
Positive Lead Measurement / Action Negative Lead C1035A-20 C175B-67 2. 7L
Positive Lead Measurement / Action Negative Lead C1035A-20 C1551B-44
Is the resistance less than 3 ohms?
Yes CLEAR codes and CARRY OUT the PCM self-test. If the concern is still present, GO to B4 No REPAIR the circuit. - Measure:
- B4 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 a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.