• | 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 |
---|---|---|---|---|
Backlight Lamp Control | B2610 00 | 2 | 1 | -- |
1. Interior Backlighting Does Not Dim 2. Interior Backlighting Inoperative |
Battery voltage is supplied at all times to the body control module (BCM) from the SWITCH DM fuse located in the rear fuse block. The BCM supplies a voltage reference through the instrument panel (I/P) dimming voltage reference circuit to the interior lamp dimmer switch, which is part of the headlamp switch. When the dimmer switch is placed in a desired brightness position, reference voltage is applied through the dimmer switch rheostat and the I/P dimming switch signal circuit to the BCM. The BCM interprets this voltage signal, then applies a variable voltage through the backlight lamp control circuits illuminating the components listed below.
• | Headlamp switch |
• | HVAC control head |
• | Diver information center (DIC) switch |
• | Clock |
• | Radio |
• | Rear HVAC control |
• | Steering wheel control switch |
• | The ignition is ON. |
• | The headlamps or park lamps ON. |
The BCM detects a short to ground on the backlight lamp control circuit.
The BCM will not DIM or illuminate any backlighting supplied by the backlight lamp control circuits.
• | The condition responsible for setting the DTC no longer exists. |
• | A history DTC will clear once 100 consecutive malfunction ignition cycles have occurred. |
Interior Lights Dimming Schematics
Interior Lighting Systems Description and Operation
Control Module References for Scan Tool Information
Ignition ON, cover the ambient light sensor. Adjust the interior lamp dimming switch from dim to full bright. The backlighting lamps should dim and then become full bright.
• | Backlight lamp control terminal 18 X3 |
• | Backlight lamp control terminal 21 X6 |
⇒ | If the DTC resets, test the control circuits for a short to ground. If the circuits test normal, replace the BCM. |
⇒ | If the DTC resets as current, test or replace the component responsible for setting the DTC. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for BCM replacement, setup, and programming |