Test Description
WARNING: This page is about a different car, the 2002 Oldsmobile Bravada, 2002 GMC Envoy XL, 2002 GMC Envoy, and 2002 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
The numbers below refer to the step numbers on the diagnostic table.
- 2: Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.
- 3: Determine if the Instrument Cluster or Powertrain Control Modules have set DTCs which may affect Engine Cooling operation are present.
- 4: The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.
- 5: If DTC P1484 or P0495 is set along with DTC P0113 and the weather conditions are cold, the cooling fan codes may be false.
Diagnostic System Check - Engine Cooling
| Step | Action | Yes | No |
|---|---|---|---|
| 1 | Install a scan tool. Does the scan tool power up? |
Go to Step 2 | Go to SCAN TOOL DOES NOT POWER UP in Data Link Communications |
| 2 |
|
Go to Step 3 | Go to SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 Device (W/O Immobilizer) in Data Link Communications |
| 3 | Select the powertrain control module display DTCs function on the scan tool. Does the scan tool display any DTCs? |
Go to Step 4 | Go to Symptoms - Engine Cooling . |
| 4 | Does the scan tool display any DTCs which begin with a "U"? | Go to SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 Device (W/O Immobilizer) in Data Link Communications | Go to Step 5 |
| 5 | Does the scan tool display DTC P0112 or P0113? | Go to DIAGNOSTIC TESTS . | Go to Diagnostic Trouble Code (DTC) List |