B2624

DTC B2624

Circuit Description

The body control module (BCM) directly sends a reference voltage to the instrument panel (I/P) dimmer switch which is then reduced based on the I/P dimmer switch position and monitored as a signal to the BCM. The BCM uses this signal to directly control the desired level of I/P illumination lamp intensity.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC 2624 Dimming Display Pulse Width Modulation (PWM) Input Circuit Open

Conditions for Running the DTC

The battery voltage must be between 9-16 volts.

Conditions for Setting the DTC

When the BCM monitors a signal voltage equal to or greater than 4.86 volts for more than one second

Action Taken When the DTC Sets

The I/P illumination lamp dimming will not operate.

Conditions for Clearing the MIL/DTC

* This DTC will clear on current status after the condition for setting the fault is corrected.
* A history DTC will clear after 100 consecutive ignition cycles without a fault present.
* History and current DTCs can be cleared using a scan tool.

Test Description

Step 1 - Step 9:

Step 10 - Step 16:

The numbers below refer to the step numbers on the diagnostic table.
3. This step tests for the proper operation of the circuit in the low voltage range.
4. This step tests for the proper operation of the circuit in the high voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to voltage.
5. This step tests for a short to voltage in the signal circuit.
6. This step tests for a high resistance or an open in the low reference circuit.