Circuit Description
The body control module (BCM) monitors the instrument panel (IP) lamps dimming control circuit to determine the lighting intensity of the IP lamps. When the BCM receives a varied voltage signal on the IP lamps dimming control circuit, it applies a corresponding pulse width modulated (PWM) voltage signal through the IP lamps supply voltage circuit to all the IP lamps.
Conditions for Running the DTC
| • | The battery voltage must be between 9 and 16 volts. |
| • | Ignition switch in the RUN position. |
| • | The headlamp switch, must be in the OFF or AUTO position and the ambient light sensor must be in the low light state. |
| • | The park brake released. |
Conditions for Setting the DTC
To set B2613, the following conditions must be present:
| • | The instrument panel lamps dimming control circuit is shorted to battery voltage. |
| • | The above conditions must be met for 1 second. |
Action Taken When the DTC Sets
The instrument panel lights remain full bright at all times.
Conditions for Clearing the MIL/DTC
| • | A current DTC will clear at the next fault free ignition cycle. |
| • | A history DTC will clear after 100 consecutive ignition cycles without a fault present. |
| • | Use a scan tool in order to clear history and current DTCs. |
Diagnostic Aids
| • | If the DTC is a history DTC, the fault maybe intermittent. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
| • | The following conditions may cause an intermittent malfunction to occur: |
| - | An intermittent short to battery positive voltage in the IP lamps dimming control circuit. |
| - | A poor connection or an intermittent open in the low reference circuit. |
| - | The IP dimmer switch is intermittently shorted to battery positive voltage. |
| - | The BCM is intermittently shorted to battery positive voltage. |
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: Interior Lights Dimming Schematics Connector End View Reference: Master Electrical Component List in Wiring Systems. | ||||
1 | Did you perform the Lighting System Diagnostic System Check? | -- | Go to Step 2 | |
2 |
Does the scan tool indicate that the dimming potentiometer parameter is within the specified range? | 0.1-13.5 V | Go to Diagnostic Aids | Go to Step 3 |
3 |
Does the scan tool indicate that the dimming potentiometer parameter is less than the specified value? | 0.1 V | Go to Step 4 | Go to Step 9 |
4 |
Does the scan tool indicate that the dimming potentiometer parameter is greater than the specified value? | 13.5 V | Go to Step 5 | Go to Step 7 |
5 |
Does the test lamp illuminate? | 0.1 V | Go to Step 6 | Go to Step 10 |
6 | Test the IP lamps low reference circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 11 |
7 | Test the IP lamp low reference circuit for a short to ground, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 8 |
8 | Test the IP lamps dimming control circuit for a short to ground, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 11 |
9 | Test the IP lamps dimming control circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 11 |
10 | Inspect for poor connections at the harness connector of the IP dimmer switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 12 |
11 | Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 13 |
12 | Replace the I/P dimmer switch. Refer to Instrument Panel Lamp Dimmer Switch Replacement . Did you complete the replacement? | -- | Go to Step 14 | -- |
13 |
Important: Perform the setup procedure for the BCM. Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System. Replace the body control module (BCM). Refer to Body Control Module Replacement in Body Control System. Did you complete the replacement? | -- | Go to Step 14 | -- |
14 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
