Circuit Description
The PCM will activate the A/C clutch relay when the PCM detects that A/C has been requested. When the PCM activates the relay, voltage should be present at both the A/C compressor clutch and the A/C clutch status circuit at the PCM.
Conditions for Running the DTC
The A/C is requested.
Conditions for Setting the DTC
The PCM commands the A/C ON and the PCM does not detect a voltage on the A/C clutch status line for more than 5.0 seconds.
Action Taken When the DTC Sets
| • | The powertrain control module (PCM) stores the DTC information into memory when the diagnostic runs and fails. |
| • | The malfunction indicator lamp (MIL) will not illuminate. |
| • | The PCM records the operating conditions at the time the diagnostic fails. The PCM stores this information in the Failure Records. |
Conditions for Clearing the DTC
| • | A last test failed, or current DTC, clears when the diagnostic runs and does not fail. |
| • | A history DTC will clear after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic. |
| • | Use a scan tool in order to clear the DTC. |
Diagnostic Aids
The following may cause an intermittent:
| • | Mis-routed harness |
| • | Rubbed through wire insulation |
| • | Broken wire inside the insulation |
For an intermittent condition, refer to Symptoms .
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step tests the operation of the A/C compressor clutch. The PCM disables the A/C compressor clutch when this DTC is set.
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Using the Freeze Frame and/or Failure Records data may aid in locating an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data can help determine how many miles since the DTC set. The Fail Counter and Pass Counter can also help determine how many ignition cycles the diagnostic reported a pass and/or a fail. Operate vehicle within the same freeze frame conditions (RPM, load, vehicle speed, temperature etc.) that you observed. This will isolate when the DTC failed.
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This step verifies whether ignition voltage is available at the relay.
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This step determines if the A/C relay is at fault or the A/C status circuit is at fault. If the A/C clutch engages, this indicates that the A/C Status circuit is OK.
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If the A/C Status is displayed as OFF, this indicates the A/C status circuit is open between the splice and the PCM. If the A/C Status is displayed as ON, this indicates a faulty connection at the A/C compressor relay or a faulty relay.
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This DTC will not report a pass. The scan tool status for this DTC will never report a pass. The scan tool will only display when the diagnostic fails. The repair is not complete if the scan tool indicates that the diagnostic ran and failed.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? | -- | ||
Does the A/C clutch operate properly? | 5 minutes | |||
Does the scan tool indicate that this diagnostic failed this ignition? | -- | Go to Diagnostic Aids | ||
|
Important: For underhood electrical center relay terminal identification, refer to Electrical Center Identification Views in Wiring Systems.
Does the test lamp illuminate? | -- | |||
Jump the ignition feed circuit to the A/C clutch status circuit (load) at the underhood electrical center 2 using a fused jumper wire. Refer to Using Fused Jumper Wires in Wiring Systems. Does the A/C clutch engage? | -- | |||
Monitor the A/C Status display on the Engine 1 Data List using the scan tool with the fused jumper still installed. Does the scan tool indicate the A/C Status as ON? | -- | |||
7 |
Important: Inspect for poor A/C clutch relay connections before replacing the relay. Refer to Wiring Repairs in Wiring Systems. Replace the A/C clutch relay. Refer to Compressor Relay Replacement in HVAC Systems Manual. Is the action complete? | -- | -- | |
8 | Repair the open A/C clutch status circuit from the splice to the PCM. Refer to Wiring Repairs in Wiring Systems. Did you find and repair the condition? | -- | ||
9 | Repair the open ignition feed circuit to A/C relay. Refer to Wiring Repairs in Wiring Systems. Is the action complete? | -- | -- | |
10 | Repair the open in A/C status circuit from A/C relay to splice. Refer to Wiring Repairs in Wiring Systems. Is the action complete? | -- | -- | |
11 |
Important:: Program the replacement PCM. Refer to Powertrain Control Module Replacement/Programming . Replace the PCM. Is the action complete? | -- | -- | |
Does the scan tool indicate that this failed? | -- | |||
13 | Select the Capture Info option and the Review Info option using the scan tool. Are any DTCs displayed that have not been diagnosed? | -- | Go to the applicable DTC table | System OK |
