B2652
DTC B2652
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* 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 3
Diagnostic Fault Information
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 through the instrument panel lamp supply voltage circuit illuminating the components listed below:
* Headlamp switch
* Climate control panel
* Rear heater switch
* Auxiliary air condition control panel - front
* Auxiliary air condition control panel - rear
* Driver and passenger window switches
* Driver and passenger door lock switches
* Tow/haul switch
* SIR disable switch
* Electronic traction control switch
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.
Circuit/System Verification
Ignition ON, park lamps ON, adjust the dimmer switch from dim to full bright. The I/P lamps should dim and then become full bright.
Circuit/System Testing
1. Ignition OFF, disconnect the X2 harness connector at the BCM.
2. Verify that a test lamp illuminates between the 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. If the circuit tests normal and the B+ circuit fuse is open, test the supply voltage circuit terminal 3 for a short to ground.
3. Ignition OFF, disconnect all of the instrument panel lamp components fed by the supply voltage circuit terminal 3.
4. Ignition ON, with a scan tool clear the DTC.
5. Operate the vehicle within the conditions for running the DTC and verify the DTC does not reset.
• If the DTC resets, test the supply voltage circuit for a short to ground. If the circuit test normal, replace the BCM.
6. Reconnect each component one at a time and verify that 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 after completing the diagnostic procedure. Verification Tests
* Headlamp Switch Replacement
* Auxiliary Blower Motor Switch Replacement
* Auxiliary Heater and Air Conditioning Control Replacement - Front
* Auxiliary Heater and Air Conditioning Control Replacement - Rear
* Front Side Door Window Switch Replacement
* Door Lock Switch Replacement
* Heater and Air Conditioning Control Replacement
* Tow/Haul Switch Replacement
* Inflatable Restraint Instrument Panel Module Disable Switch Replacement
* Electronic Traction Control Switch Replacement