• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Hazard Switch Signal | 1 | 1 | 1 | -- |
I/P Lamps Dimmer Switch Signal | 2 | 2 | 2 | -- |
Hazard Switch Ground | -- | 1 | -- | -- |
1. Hazard Lamps Malfunction 2. Interior Backlighting Malfunction |
The hazard flashers may be activated in any power mode. The hazard switch is permanently grounded through G200. When the hazard switch is placed in the ON position, ground is applied through the hazard switch signal circuit to the body control module (BCM). The BCM supplies battery voltage to all four turn signal lamps in an ON and OFF duty cycle. When the hazard switch is activated, the BCM sends a serial data message to the instrument panel cluster (IPC) requesting both turn signal indicators to be cycled ON and OFF.
Exterior Lighting Systems Description and Operation
Control Module References for scan tool information
⇒ | If the test lamp does not illuminate, test the ground circuit for an open/high resistance. |
⇒ | If not the specified value, test the signal circuit terminal D for a short to ground. If the circuit tests normal, replace the BCM. |
⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM. |
Ignition ON, with a scan tool perform the Display Test for the instrument panel cluster (IPC) and observe both turn signal indicators.
⇒ | If both turn signal indicators illuminate during the test, replace the BCM. |
⇒ | If both turn signal indicators do not illuminate during the test or remain illuminated at all times, replace the IPC. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for BCM or IPC replacement, setup, and programming |