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Diagnostic Test

WARNING: This page is about a different car, the 2009 Dodge Caliber. However, it is still accessible from the selected car via links, so may be relevant.
  1. DTC IS ACTIVE 
    1. Start the engine and allow it to reach normal operating temperature.
    2. Turn the Air Conditioning on.
      WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.
    3. With the scan tool, select View DTCs.

      Is the status Active for this DTC?

      Yes 

      • Go to step  2

      No 

  2. (Z909) GROUND CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 1: Checking Ground Circuit
    GC0099998Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Disconnect the A/C Compressor connector.
    3. Turn the ignition on.
    4. Using a 12-volt test light connected to 12 volts, check the (Z909) Ground circuit in the A/C Compressor harness connector.
      NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

      Is the test light illuminated and bright?

      Yes 

      • Go to step  3

      No 

  3. (C27) A/C COMPRESSOR CONTROL CIRCUIT SHORTED TO GROUND 
    Fig 2: Checking A/C Compressor Control Circuit
    GC0100000Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Disconnect the Powertrain Control Module (PCM) harness connector.
    3. Measure the resistance between ground and the (C27) A/C Compressor Control circuit in the A/C Compressor harness connector.

      Is the resistance below 100 Ohms?

      Yes 

      No 

      • Go to step  4
  4. (C27) A/C COMPRESSOR CONTROL CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 3: Checking A/C Compressor Control Circuit
    GC0100001Courtesy of CHRYSLER LLC
    1. Measure the resistance of the (C27) A/C Compressor Control circuit between the A/C Compressor harness connector and the Powertrain Control Module (PCM) harness connector.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Go to step  5

      No 

  5. A/C COMPRESSOR 
    Fig 4: Checking A/C Compressor Control Circuit
    GC0100002Courtesy of CHRYSLER LLC
    1. Connect the Powertrain Control Module (PCM) harness connector.
    2. Turn the ignition on.
    3. With the scan tool, actuate the A/C Compressor control to the ON position.
    4. Using a 12-volt test light connected to ground, check the (C27) A/C Compressor Control circuit in the A/C Compressor harness connector.
      NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
    5. With the scan tool, actuate the A/C Compressor control to the OFF position.
    6. Using a 12-volt test light connected to ground, check the (C27) A/C Compressor Control circuit in the A/C Compressor harness connector.
      NOTE: The test light should not be illuminated.

      Is the test light illuminated and bright with the actuation ON (100%) and not illuminated with the actuation OFF (0%)?

      Yes 

      No 

      • Go to step  6
  6. POWERTRAIN CONTROL MODULE (PCM) 
    1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the A/C Compressor and the Powertrain Control Module (PCM).
    2. Look for any chafed, pierced, pinched, or partially broken wires.
    3. Look for broken, bent, pushed out or corroded terminals.
    4. Refer to any Technical Service Bulletins that may apply.

      Were any problems found?

      Yes 

      No 

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