Conditions for Clearing the DTC
WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- A current DTC Last Test Failed clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
- Clear the DTC with a scan tool.
DTC P1AC0
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Engine Cooling Schematics Connector End View Reference: Cooling System Connector End Views |
|||
| 1 | Was the Engine Cooling Diagnostic System Check performed? | Go to Step 2 | Go to Diagnostic System Check - Engine Cooling |
| 2 |
|
Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
| 3 |
|
Go to Step 4 | Go to Step 5 |
| 4 | Test the SGCM coolant pump/fan 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 9 | Go to Step 6 |
| 5 |
IMPORTANT:
Ensure to inspect the terminals in the electrical center. Inspect for poor connections at the connector of the SGCM coolant pump/fan 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 9 | Go to Step 7 |
| 6 | Inspect for poor connections at the harness connector of the SGCM. 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 9 | Go to Step 8 |
| 7 | Replace the SGCM coolant pump/fan relay. Refer to Relay Replacement (Within an Electrical Center)
or Relay Replacement (Attached to Wire Harness)
in Wiring Systems. Did you complete the replacement? |
Go to Step 9 | - |
| 8 |
IMPORTANT:
Perform the programming procedure for the SGCM. Replace the SGCM. Refer to Starter/Generator Control Module (SGCM) Replacement (5.3L Engine w/RPO HP2)
in Engine Electrical.Did you complete the replacement? |
Go to Step 9 | - |
| 9 |
|
Go to Step 2 | System OK |