Coolant Heater Inoperative
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2004 GMC Yukon XL, 2004 GMC Yukon, 2004 Chevrolet Tahoe, 2004 Chevrolet Suburban, and 2004 Cadillac Escalade EXT. However, it is still accessible from the selected car via links, so may be relevant.
Coolant Heater Inoperative
| Step | Action | Yes | No |
|---|---|---|---|
| 1 | Did you perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Engine Cooling |
| 2 | Test the engine coolant heater power supply cord for an open or short to ground. Refer to Circuit Testing
in Wiring Systems. Did you find a condition? |
Go to Step 3 | Go to Step 4 |
| 3 | Replace the engine coolant heater power supply cord. Refer to Coolant Heater Cord Replacement . Did you complete the repair? |
Go to Step 6 | - |
| 4 | Inspect for poor connections at the harness connector of the engine coolant heater. 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 6 | Go to Step 5 |
| 5 | Replace the engine coolant heater. Refer to Coolant Heater Replacement (Dealer Installation - 6.0L Engine) or Coolant Heater Replacement (4.8L, 5.3L, and 6.0L Engines) or Coolant Heater Replacement (8.1L Engine) . Did you complete the repair? |
Go to Step 6 | - |
| 6 | Operate the system in order to verify the repair. Did you correct the condition? |
System OK | Go to Step 2 |