Diagnostic Aids
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.
- When the instrument cluster detects low voltage at the ignition 1 voltage circuit, the instrument cluster will not communicate with the scan tool, and the odometer and PRNDL displays will not be illuminated. The season odometer will display if the trip reset switch is pressed, and the instrument cluster will communicate with the scan tool until the trip reset switch is released.
- An intermittent condition is likely to be caused by an open condition in the ignition 1 voltage circuit.
- DTC B1372 can only be read by the scan tool as a history code once the fault is removed. Refer 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 for diagnosis of a loss of communication with the instrument cluster.
DTC B1372 Diagnostic Table
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Instrument Cluster Schematics Connector End View Reference: Instrument Panel, Gages, and Console Connector End Views |
|||
| 1 | Did you perform the Instrument Cluster Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Instrument Cluster |
| 2 | Test the ignition 1 voltage circuit for an open or high resistance. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
Go to Step 5 | Go to Step 3 |
| 3 | Inspect for poor connections at the harness connector of the instrument panel cluster (IPC). 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 5 | Go to Step 4 |
| 4 |
IMPORTANT:
Program the replacement IPC. Replace the IPC. Refer to Instrument Panel Cluster (IPC) Replacement .Did you complete the replacement? |
Go to Step 5 | - |
| 5 | Operate the system in order to verify the repair. Did you correct the condition? |
System OK | Go to Step 2 |