GM Service Manual Online
For 1990-2009 cars only

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 B2610 00 : Passenger Compartment Dimming 1 Circuit

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Body Control Module (BCM) 1 Fuse B+

B1395 03

B1395 03

--

--

I/P Dimming Voltage Reference

B1395 03

B2652 00

B1395 07

--

I/P Dimmer Switch Signal

B1395 03

1

1

--

I/P Lamps Dimmer Switch Signal

B2652 00

1

1

--

Indicator Dimming Control

B2625 00

1

1

--

LED Backlight Dimming Control

B2610 00

1

1

--

I/P Dimmer Switch Low Reference

--

1

--

--

I/P Dimmer Switch Ground

--

1

--

--

1. Interior Backlighting Malfunction

Circuit/System Description

The instrument panel (I/P) 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 light 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.

Conditions for Running the DTC

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

Conditions for Setting the DTC

DTC B2610 00 will set when the BCM detects a short to ground in the LED backlight dimming control circuit.

Actions Taken When the DTC Sets

The BCM will not dim or illuminate any indicators supplied by the LED backlight dimming control 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

Connector End View Reference

Component Connector End Views

Description and Operation

Interior Lighting Systems Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

  1. With a scan tool clear the DTC.
  2. Ignition OFF, disconnect the harness connectors at the components fed by the I/P lamps dimmer switch control circuit.
  3. Operate the vehicle within the conditions for running the DTC and verify the DTC does not reset.
  4. If the DTC resets, test the LED backlight dimming control circuit for a short to ground. If the circuits test normal, replace the BCM.
  5. Reconnect each component one at a time and verify that the DTC does not reset as current.
  6. 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.

    •  Driver Information Display Switch Replacement
    •  Instrument Panel Lamp Dimmer Switch Replacement
    •  Clock Replacement
    •  Control Module References for BCM, HVAC control module, or Radio replacement, setup, and programming