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Home >> Alfa Romeo >> 2019 >> Giulia Base, AWD >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> 2.0L - DTCS P1128-00 To P1E39-00 >> DTC Troubleshooting >> P164E-00-A/C Clutch Relay Control Range/Performance >> Diagnostic Test

Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    1. With the scan tool, read Powertrain Control Module (PCM) DTCs and Freeze Frame Data and record on the repair order.
    2. Using the recorded Freeze Frame Data and the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
    3. With the scan tool, read PCM DTCs.

      Is the DTC active or pending?

      Yes 

      • Go To  2

      No 

  2. CHECK THE A/C CLUTCH RELAY 
    1. Turn the ignition off.
    2. Install a known good relay in place of the existing A/C Clutch Relay.
    3. Using the recorded Freeze Frame Data and the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
    4. With the scan tool, read PCM DTCs.

      Is the DTC active or pending?

      Yes 

      • Go To  3

      No 

  3. CHECK THE A/C COMPRESSOR CLUTCH OPERATION 
    1. Start the engine and raise the engine speed above 700 RPM.
    2. Using the HVAC Controls, turn the A/C OFF for greater than 10 seconds and note if the compressor clutch is engaged.
    3. Using the HVAC Controls, turn the A/C ON for greater than 10 seconds and note if the compressor clutch is engaged.

      Does the A/C Compressor Clutch:

      Stay on when commanded off 

      • Go To  6

      Stay off when commanded on 

      • Go To  4

      Cycles off and on properly when commanded 

      • Go To  10
  4. CHECK THE (C3) FUSED B(+) CIRCUIT FOR AN OPEN OR HIGH RESISTANCE 
    1. Turn the ignition off.
    2. Remove the A/C Clutch Relay from the PDC.
    3. With a 12-volt test light connected to ground, probe the (C3) Fused B(+) circuit at the PDC relay connector.
      NOTE:

      The test light must 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  5

      No 

      • Repair the (C3) Fused B(+) circuit for an open or high resistance.

        If the fuse is open Go To  6

      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  5. CHECK THE A/C CLUTCH 
    1. Connect a jumper wire between the (C3) Fused B(+) circuit and the (C281) A/C Clutch Control Output circuit at the A/C Clutch Relay PDC connector.

      Does the Compressor Clutch engage (audible click)?

      Yes 

      • Go To  10

      No 

      • Go To  7
  6. CHECK THE (C3) A/C CLUTCH CONTROL CIRCUIT FOR A SHORT TO GROUND 
    1. Disconnect the A/C Clutch harness connector.
    2. With a 12-volt test light connected to ground, probe the (C3) A/C Clutch Control Output circuit at the A/C Clutch harness connector.

      Is the test light illuminated and bright?

      Yes 

      • Repair the (C3) A/C Clutch Control Output circuit for a short to ground.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Replace the A/C Compressor Clutch Coil in accordance with the Service Information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  7. CHECK THE (C3) A/C CLUTCH CONTROL CIRCUIT FOR AN OPEN OR HIGH RESISTANCE 
    1. Disconnect the A/C Clutch harness connector.
    2. With a 12-volt test light connected to ground, probe the (C3) A/C Clutch Control Output circuit at the A/C Clutch harness connector.

      Is the test light illuminated and bright?

      Yes 

      • Go To  8

      No 

      • Repair the (C3) A/C Clutch Control Output circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  8. CHECK THE (K900) A/C CLUTCH GROUND CIRCUIT FOR AN OPEN OR HIGH RESISTANCE 
    1. Disconnect the jumper from the A/C Clutch Relay PDC connector.
    2. With a 12-volt test light connected to Battery (+), probe the (K900) A/C Clutch Ground circuit at the A/C Clutch harness connector.

      Is the test light illuminated and bright?

      Yes 

      • Refer to  10.

      No 

      • Repair the (K900) A/C Clutch Ground circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  9. CHECK THE (C281) A/C CLUTCH CONTROL CIRCUIT FOR A SHORT TO VOLTAGE 
    1. Turn the ignition on.
    2. Measure the voltage of the (C281) A/C Clutch Control Output circuit at the A/C Clutch Relay PDC connector.

      Is there any voltage present?

      Yes 

      • Repair the (C281) A/C Clutch Control Output circuit for a short to voltage.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  10
  10. CHECK THE A/C SYSTEM 
    1. Check the A/C System for the following but not limited to:
      • Low refrigerant level.
      • Faulty Compressor Clutch Coil.
      • Improper Clutch gap between the Face Plate and Pulley Hub.
      • Compressor Clutch Pulley Hub Snap Ring broken or missing.
      • Face Plate Shaft Key sheared or missing.
      • Broken Face Plate.
      • Compressor not pumping.
      • Frozen Compressor.

      Were any problems found?

      Yes 

      • Repair as necessary in accordance with the Service Information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  11
  11. CHECK RELATED PCM AND COMPONENT CONNECTIONS 
    1. Disconnect all PCM harness connectors.
    2. Disconnect all related in-line harness connections (if equipped).
    3. Disconnect the related component harness connectors.
    4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
      • Proper connector installation.
      • Damaged connector locks.
      • Corrosion.
      • Other signs of water intrusion.
      • Weather seal damage (if equipped).
      • Bent terminals.
      • Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
      • Terminals that have been pushed back into the connector cavity.
      • Check for spread terminals and verify proper terminal tension.

      Repair any conditions that are found.

    5. Connect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
    6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
    7. Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
    8. With the scan tool, erase DTCs.
    9. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
    10. With the scan tool, read DTCs.

      Did the DTC return?

      Yes 

      No 

      • The wiring or poor connection problem has been repaired.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .