Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: HVAC Compressor Control Schematics . DEFINITION: A/C compressor clutch will not disengage when no A/C request has been made and no Powertrain DTC has been set. | ||||
1 | Did you review the HVAC operation and perform the necessary inspections? | -- | Go to Step 2 | Go to Symptoms |
2 |
Does the A/C compressor operate? | -- | 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 parameter in the Powertrain data list. Does the scan tool indicate that the A/C request parameter is ON? | -- | 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 parameter is ON? | -- | 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 A/C compressor clutch relay terminals. Does the resistance measurement equal the specified value? | OL | Go to Step 8 | Go to Step 10 |
8 | Test the A/C 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. | -- | Go to Step 17 | Go to Step 13 |
11 | Inspect for poor connections at the harness connector of the HVAC control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. | -- | 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. | -- | Go to Step 17 | Go to Step 16 |
13 | Replace the A/C compressor clutch relay. 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 module. Refer to Control Assembly Replacement . Did you complete the replacement? | -- | Go to Step 17 | -- |
16 |
Important:: Perform the reprogramming procedure for the PCM. Replace the Vehicle Control Module (VCM) or Powertrain Control Module (PCM). Refer to VCM Replacement/Programming in Engine Controls - 4.3L Powertrain Control Module Replacement in Engine Controls - 4.8L, 5.3L, and 6.0L. 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 |
