B2652

DTC B2652

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

DTC Descriptor
DTC B2652 00
- Passenger Compartment Dimming 3 Circuit

Diagnostic Fault Information





Circuit/System Description

The instrument panel (I/P) lamp dimmer switch is used to increase and decrease the brightness of the interior backlighting components. The I/P dimmer switch provides a voltage signal that will increase as the brightness of the lights are increased and decrease as the brightness of the lights are decreased. The body control module (BCM) provides a low reference signal and a B+ voltage reference to the I/P dimmer switch. When the I/P dimmer switch is placed in the desired position, the dimmed voltage setting is applied from the I/P dimmer switch through the I/P dimmer switch signal circuit to the BCM. The BCM interprets the signal and applies the dimmed voltage to the I/P lamps supply voltage circuit and the interior backlighting components dim to the requested level. Ground for the I/P dimmer switch is provided at G200.

Conditions for Running the DTC

* Battery voltage must be between 9-16 volts.
* Park lamps ON.

Conditions for Setting the DTC

DTC B2652 00 will set for the following conditions:

* The BCM detects a short to ground in the I/P lamps dimmer switch signal circuit.
* The BCM detects a short to ground or an open/high resistance in the BCM 7 fuse B+ circuit.

Actions Taken When the DTC Sets

The BCM will not DIM or illuminate any I/P lamps supplied by the I/P lamps dimmer switch signal circuit.

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 (Interior Lights Dimming Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Interior Lighting Systems Description and Operation (Interior Lighting Systems Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the X2 harness connector at the BCM.
2. Verify a test lamp illuminates between the BCM 7 fuse B+ circuit terminal 2 and ground.

• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

3. Reconnect the X2 harness connector at the BCM.
4. Ignition ON, with a scan tool clear all DTCs.
5. Ignition OFF, disconnect the harness connectors at the following components:

* Power window switch - left rear
* Power window switch - right rear
* PRNDL lamp
* Sunroof control switch
* Sunroof shade switch

6. Ignition ON, operate the vehicle within the conditions for running the DTC and verify the DTC does not reset.

• If the DTC resets, test the appropriate signal circuit terminal listed below for a short to ground. If the circuit tests normal, replace the BCM.

* Power window switch - left rear terminal A
* Power window switch - right rear terminal A
* PRNDL lamp terminal A
* Sunroof control switch terminal A
* Sunroof shade switch terminal A

7. Reconnect each component one at a time and verify the DTC does not reset as current.

• If the DTC resets as current, test or replace the component responsible for setting the DTC.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Rear Side Door Window Switch Replacement (Rear Side Door Window Switch Replacement)
* Sunroof Switch Replacement (Service and Repair)
* Automatic Transmission Control Indicator Replacement (Service and Repair)
* Sunroof Sunshade Switch Replacement (Sunroof Sunshade Switch Replacement)
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming