Diagnostic Test

WARNING: This page is about a different car, the 2012 RAM Pickup and 2012 RAM Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

A/C COMPRESSOR CLUTCH OPERATION
NOTE:
If Powertrain Control Module (PCM) DTC P0645-A/C CLUTCH CONTROL CIRCUIT is present, diagnose it first.
1. Ignition on, engine not running.
2. With the scan tool, actuate the A/C Clutch.
  Does the A/C Clutch actuate?
  
  Yes
  - Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 2.
CHECK THE (C3) A/C CLUTCH CONTROL OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE

Fig 1: Checking A/C Clutch Control Output Circuit For A Short To Voltage
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition off.
2. Disconnect the A/C Compressor Clutch harness connector.
3. Disconnect the TIPM C1 harness connector.
4. Ignition on, engine not running.
5. Measure the voltage between ground and the (C3) A/C Clutch Control Output circuit at the A/C Compressor Clutch harness connector.
  Is there any voltage present?
  
  Yes
  - Repair the short to voltage in the (C3) A/C Clutch Control Output circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 3.
CHECK THE TIPM FOR CORRECT OPERATION

Fig 2: Checking A/C Clutch Control Output For Correct Operation
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition off.
2. Reconnect the TIPM C1 harness connector.
3. Ignition on, engine not running.
4. Connect a 12-volt test light between the (C3) A/C Clutch Control Output circuit and (Z908)/(Z916) Ground circuit at the A/C Compressor Clutch harness connector.
5. With the scan tool, actuate the A/C Clutch.
  Does the test light illuminate when the A/C Clutch is commanded on?
  
  Yes
  - Verify that there is good pin to terminal contact in the A/C Compressor Clutch and TIPM connectors. If OK, replace the A/C Compressor Clutch in accordance with the Service Information. Refer to COMPRESSOR, A/C, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 4.
CHECK THE (C3) A/C CLUTCH CONTROL OUTPUT CIRCUIT FOR AN OPEN

Fig 3: Checking A/C Clutch Control Output Circuit For An Open
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition off.
2. Disconnect the TIPM C1 harness connector.
3. Measure the resistance of the (C3) A/C Clutch Control Output circuit between the A/C Compressor Clutch harness connector and the TIPM C1 harness connector.
  Is the resistance below 5.0 Ohms?
  
  Yes
  - Go To 5.
  No
  - Repair the open in the (C3) A/C Clutch Control Output circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE (Z908)/(Z916) GROUND CIRCUIT FOR AN OPEN

Fig 4: Checking A/C Clutch Ground Circuit For An Open
Courtesy of CHRYSLER GROUP, LLC
1. Using a 12-volt test light connected to 12-volts, check the (Z908)/(Z916) Ground circuit at the A/C Compressor Clutch harness connector.
  Does the test light illuminate brightly?
  
  Yes
  - Go To 6.
  No
  - Repair the open or excessive resistance in the (Z908)/(Z916) Ground circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
TOTALLY INTEGRATED POWER MODULE (TIPM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the A/C Clutch and TIPM.
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the A/C Compressor Clutch and TIPM connectors.
4. Perform any Technical Service Bulletins (TSB)s that may apply.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Replace the TIPM in accordance with the Service Information. Refer to MODULE, TOTALLY INTEGRATED POWER (TIPM), REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .