The body control module (BCM) applies a 12-volt reference voltage through the headlamp and panel dimmer switch 12-volt reference circuit to the headlamp and panel dimmer switch. When the dimming switch is placed in the desired position, the dimmed voltage setting is applied from the headlamp and panel dimmer switch through the instrument panel (I/P) lamp dimming switch signal circuit to the BCM. The BCM then applies the dimmed voltage to the I/P lamp dimming control circuit and the components on the circuit.

The ignition is ON.

The BCM receives an open, voltage, or ground signal on the I/P lamp dimming control circuit.

The I/P lamps are not illuminated.

Schematic Reference

Interior Lights Dimming Schematics

Connector End View Reference

Lighting Systems Connector End Views

Electrical Information Reference

Scan Tool Reference

Ignition ON and park lamps ON, vary the headlamp and panel dimmer switch from dim to full bright. The I/P lamps should dim and then become full bright.

1. Ignition OFF, park lamps OFF, disconnect all of the lamp components on the I/P lamp dimming control circuit. Verify DTC B2652 00 does not set.

⇒	If the DTC resets, test for a short to voltage, short to ground, or an open in the I/P lamp dimming control circuit and for an open in the dimmer switch 5-volt reference circuit. If the circuit/connections test normal, replace the BCM.

2. Reconnect each component one at a time and test for the DTC B2652 00.

⇒	If the DTC resets, replace that particular component.

⇒	If the DTC does not reset, replace the BCM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.