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.
- 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.
Diagnostic System Check - Audible Warnings
| 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 display DTCs function on the scan tool for the following control modules:
Does the scan tool display any DTCs? |
Go to Step 4 | Go to Symptoms - Instrument Panel, Gages and Console |
| 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 B1000, B1397, or B1440? | Go to DIAGNOSTIC TROUBLE CODE (DTC) LIST in Body Control System | Go to Diagnostic Trouble Code (DTC) List |