Diagnostic Instructions
| • | 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. |
DTC Descriptor
DTC B2652 00: Passenger Compartment Dimming 3Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
B+, BCM X2 Terminal 2 | B2652 00 | B2652 00 | -- | -- |
I/P Lamps Supply Voltage | B2652 00 | 2 | 1 | -- |
1. Interior Backlighting Does Not Dim 2. Interior Backlighting Inoperative | ||||
Circuit/System Description
The body control module (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 position, reference voltage is applied through the dimmer switch rheostat and the I/P lamps dimmer switch signal circuit to the BCM. The BCM interprets this voltage signal, then applies a pulse width modulated (PWM) voltage, supplied by the SWITCH DM Fuse located in the rear fuse block, through the instrument panel lamp supply voltage circuits illuminating the components listed below.
| • | Ashtray Lamp |
| • | Headlamp Switch |
| • | Hazard Switch |
| • | I/P Cluster |
| • | Power Window Switches-Rear Doors |
| • | Sunroof Switch |
| • | TCS Switch |
| • | Reverse Lockout Solenoid |
| • | Garage Door Opener Transmitter |
Conditions for Running the DTC
| • | The ignition is ON. |
| • | The headlamps or park lamps ON. |
Conditions for Setting the DTC
The BCM detects a short to ground on the instrument panel lamps supply voltage circuit.
Action Taken When the DTC Sets
The BCM does not attempt to illuminate the instrument panel lamps.
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists. |
| • | A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred. |
Reference Information
Schematic Reference
Interior Lights Dimming Schematics
Connector End View Reference
Description and Operation
Interior Lighting Systems Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for Scan Tool Information
Circuit/System Verification
Ignition ON, cover the ambient light sensor, vary the interior lamp dimming switch from dim to full bright. The I/P lamps should dim and then become full bright.
Circuit/System Testing
- Ignition OFF, disconnect the X2 harness connector at the BCM.
- Verify that a test lamp illuminates between the B+ circuit terminal 2 and ground.
- Ignition OFF, connect the X2 harness connector to the BCM.
- Disconnect the harness connectors at all components fed by the BCM supply voltage circuits listed below.
- Ignition ON, clear the DTC with a scan tool.
- Operate the system within the Conditions for Running the DTC and verify the DTC does not reset.
- Reconnect each component one at a time and verify that the DTC does not reset.
| ⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test the supply voltage circuits listed below for a short to ground. |
| • | Instrument panel lamp supply voltage circuit terminal 3 X2 |
| • | Instrument panel lamp supply voltage circuit terminal 3 X6 |
| • | Instrument panel lamp supply voltage circuit terminal 3 X2 |
| • | Instrument panel lamp supply voltage circuit terminal 3 X6 |
| ⇒ | If the DTC resets, test the supply voltage circuits for a short to ground. If the circuits test normal, replace the BCM. |
| ⇒ | If the DTC resets, test or replace the component responsible for setting the DTC. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
