HVAC Compressor Clutch Does Not Disengage 4.3L
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: HVAC Schematics Connector End View Reference: HVAC Connector End Views DEFINITION: The A/C compressor clutch will not disengage when an A/C request has not been made and a Powertrain DTC has not been set. | ||||
1 | Did you review the HVAC operation and perform the necessary inspections? | -- | Go to Step 2 | |
2 |
Does the A/C compressor clutch engage? | -- | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
3 | With a scan tool, observe the A/C Request Signal parameter in the powertrain Engine Data 2 list. Does the scan tool indicate that the A/C Request Signal parameter is YES? | -- | Go to Step 4 | Go to Step 6 |
4 | Test the A/C request signal circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 5 |
5 |
Does the scan tool indicate that the A/C Request Signal parameter is YES? | -- | Go to Step 12 | Go to Step 11 |
6 | Remove the A/C compressor clutch relay. Does the A/C compressor clutch turn OFF? | -- | Go to Step 7 | Go to Step 9 |
7 | Measure the resistance between the switch side of the A/C compressor clutch relay terminals. Does the resistance measurement equal the specified value? | ∞ | Go to Step 8 | Go to Step 10 |
8 | Test the A/C compressor clutch relay control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 12 |
9 | Test the A/C compressor clutch supply voltage circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 14 |
10 | Inspect for poor connections at the A/C compressor clutch relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 13 |
11 | Inspect for poor connections at the harness connector of the HVAC control assembly. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 15 |
12 | Inspect for poor connections at the harness connector of the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 17 | Go to Step 16 |
13 | Replace the A/C compressor clutch relay. Refer to Compressor Relay Replacement in Heating, Ventilation and Air Conditioning. Did you complete the replacement? | -- | Go to Step 17 | -- |
14 | Replace the A/C compressor clutch. Refer to Compressor Clutch Plate and Hub Assembly Removal and Compressor Clutch Plate/Hub Assembly Install in Heating, Ventilation, and Air Conditioning. Did you complete the replacement? | -- | Go to Step 17 | -- |
15 | Replace the HVAC control assembly. Refer to Heater and Air Conditioning Control Replacement . Did you complete the replacement? | -- | Go to Step 17 | -- |
16 |
Important: Perform the programming procedure for the PCM. Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls - 4.3L. Did you complete the replacement? | -- | Go to Step 17 | -- |
17 | Operate the system in order to verify the repair. Did you correct the condition? | -- | System OK | Go to Step 3 |
