Test Description
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2004 Oldsmobile Bravada, 2004 GMC Envoy XUV, 2004 GMC Envoy XL, 2004 GMC Envoy, and 2004 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: Checks for DTCs for each module of the system.
- 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 - Navigation System
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Navigation System Schematics | |||
| 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)Scan Tool Does Not Communicate with Class 2 Device (W/ Immobilizer) in Data Link Communications |
| 3 | Select the display DTCs function on the scan tool for the navigation radio. Does the scan tool display any DTCs? |
Go to Step 4 | Go to Symptoms - Navigation Systems |
| 4 | Does the scan tool display any DTCs which begin with a "U"? | Go to Step 5 | Go to Step 6 |
| 5 | Does the scan tool display U2153? | Go to Diagnostic Trouble Code (DTC) List | Go to Scan Tool Does Not Communicate with Class 2 Device (W/O Immobilizer)Scan Tool Does Not Communicate with Class 2 Device (W/ Immobilizer) in Data Link Communications |
| 6 | Does the scan tool display DTC B1000, B1004, B1007, or B1009? | Go to Diagnostic Trouble Code (DTC) List in Body Control System | Go to Step 7 |
| 7 | Does the scan tool display DTC B1327 or B1328? | Go to Diagnostic Trouble Code (DTC) List in Engine Electrical | Go to Diagnostic Trouble Code (DTC) List |