Test AV: Air Conditioning (A/C) Relay Control Circuit
PINPOINT TEST AV: AIR CONDITIONING (A/C) RELAY CONTROL CIRCUITFlow Chart:
This pinpoint test is intended to diagnose only the following:
- A/C clutch relay
- A/C clutch relay control circuit
- powertrain control module (PCM)
Air Conditioning Clutch (A/CC) Relay Connector
Air Conditioning Clutch (A/CC) Relay Connector:
PCM Connector
PCM Connector:
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AV1 : PRELIMINARY DIAGNOSIS DIAGNOSTIC TROUBLE CODE (DTC) P0645
- Carry out a visual inspection.
- Retrieve and record all DTCs.
- Clear all DTCs
- Carry out the on-demand self-test
- Is DTC P0645 present?
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AV2 : DTC P0645
- Possible causes:
- A/C clutch relay control circuit short to voltage
- A/C clutch relay control circuit open
- A/C clutch relay control circuit short to ground
- A/C clutch relay circuit
- A/C clutch relay
- PCM
- Ignition ON, engine OFF.
- Access the PCM and monitor the ACCS PID.
- Cycle the A/C control switch off and on
- Does the ACCS PID indicate ON with the A/C control switch ON and OFF with the A/C control switch OFF?
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AV3 : CHECK THE A/C CLUTCH RELAY COIL POWER CIRCUIT FOR VOLTAGE
NOTE: Refer to the Wiring Diagrams for the A/C clutch relay coil pin locations.
- Ignition OFF.
- A/CC Relay connector disconnected.
- Ignition ON, engine OFF.
- Measure the voltage between:
- Is the voltage greater than 10 V?
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AV4 : CHECK THE A/C CLUTCH RELAY CONTROL CIRCUIT
- Connect a non-powered test lamp between:
- Ignition ON, engine running.
- Cycle the A/C control switch off and on
- Is the test lamp illuminated with the A/C control switch on and is the test lamp off with the A/C control switch off?
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AV5 : CHECK THE A/C CLUTCH RELAY CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- PCM connector disconnected.
- Ignition ON, engine OFF.
- Measure the voltage between:
- Is the voltage less than 0.2 V?
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AV6 : CHECK THE A/C CLUTCH RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between:
- Is the resistance greater than 10 kOhm?
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AV7 : CHECK THE A/C CLUTCH RELAY CONTROL CIRCUIT FOR AN OPEN
- Measure the resistance between:
- Is the resistance less than 5 Ohm?
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AV8 : CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Visually inspect for:
- pushed out pins
- corrosion
- Connect all the PCM connectors and make sure they seat correctly.
- Carry out the PCM self-test and verify the concern is still present.
- Is the concern still present?
