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 in Wiring Systems.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Interior Lights Dimming Schematics Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views in Computer/Integrating Systems | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
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 in Wiring Systems. 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 in Wiring Systems. 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 in Computer/Integrating Systems 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 |
