Circuit Description
The body control module (BCM) applies a 10-volt reference through the instrument panel (I/P) dimming voltage reference circuit to the I/P dimming switch. When the switch is placed to the desired position, the dimmed voltage setting is applied from the I/P dimming switch through the I/P dimming signal circuit to the BCM. The BCM applies the dimmed voltage to the I/P lamps supply voltage circuit.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B2610 I/P Dimming Circuit
Conditions for Running the DTC
The battery voltage must be between 9-16 volts.
Conditions for Setting the DTC
| • | When the BCM receives a instrument panel controls illumination lamp request signal and the instrument panel dimming reference circuit is shorted to ground, open or short to battery positive voltage. |
| • | When the BCM is not receiving a instrument panel controls illumination lamp request signal and the instrument panel lamps dimming signal circuit is shorted to voltage or open. |
Action Taken When the DTC Sets
The instrument panel illumination lamps and the controls illumination lamps will not operate or are always ON.
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. |
Diagnostic Aids
Perform a visual inspection for loose or poor connections at all related components. Refer to Testing for Intermittent Conditions and Poor Connections .
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Interior Lights Dimming Schematics Connector End View Reference: Lighting Systems Connector End Views or Lighting Systems Connector End Views | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
2 | Test the instrument panel (I/P) lamps dimming reference circuit for an open, high resistance, short to battery positive voltage or short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 7 | Go to Step 3 |
3 | Test the I/P dimming signal circuit for a short to battery positive voltage or an open. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 7 | Go to Step 4 |
4 |
Does the DMM reading change values? | Go to Step 6 | Go to Step 5 |
5 | Replace the headlamp I/P dimmer switch. Refer to Instrument Panel Lamp Dimmer Switch Replacement . Did you complete the repair? | Go to Step 7 | -- |
6 | Replace the BCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 7 | -- |
7 |
Does the DTC reset? | Go to Step 2 | System OK |
