Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC B3600 03 : Dimmed Illumination Switch Circuit Low VoltageDTC B3600 07 : Dimmed Illumination Switch Circuit High Voltage
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
I/P Dimmer Switch Signal | B3600 03 | B3600 03 | B3600 07 | -- |
Headlamp Switch Low Reference | -- | 1 | -- | -- |
1. Headlamps Malfunction | ||||
Circuit/System Description
The instrument panel (I/P) lamp dimmer switch is incorporated into the headlamp switch assembly. The I/P dimmer switch is used to increase and decrease the brightness of the interior backlighting components. The I/P dimmer switch provides a voltage signal that will increase as the brightness of the lights are increased and decrease as the brightness of the lights are decreased. The instrument panel cluster (IPC) provides a low reference signal and a 12-volt reference to the I/P dimmer switch. When the I/P dimmer switch is placed in the desired position, the dimmed voltage setting is applied from the I/P dimmer switch through the I/P dimmer switch signal circuit to the IPC. The IPC interprets the signal and applies the dimmed voltage to the I/P lamps supply voltage circuit and the interior backlighting components dim to the requested level. Ground for the I/P dimmer switch is provided at the headlamp switch low reference circuit through the IPC.
Conditions for Running the DTC
| • | Battery voltage must be between 9-16 volts. |
| • | Park lamps ON. |
Conditions for Setting the DTC
B3600 03
The DTC will set when the IPC detects a short to ground or an open/high resistance in the I/P dimmer switch signal circuit.
B3600 07
The DTC will set when the IPC detects a short to voltage in the I/P dimmer switch signal circuit.
Actions Taken When the DTC Sets
| • | The I/P dimmer switch will not operate. |
| • | The I/P dimming lamps will not illuminate. |
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists. |
| • | A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred. |
Reference Information
Schematic Reference
Interior Lights Dimming Schematics
Connector End View Reference
Description and Operation
Interior Lighting Systems Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- With a scan tool clear the DTC.
- Ignition OFF, disconnect the harness connector at the headlamp switch.
- Ignition OFF, verify a test lamp illuminates between B+ and the low reference circuit terminal 11.
- Verify the scan tool Switch Illumination Dimming parameter displays DISABLED or INVALID.
- Install a 3A fused jumper wire between the signal circuit terminal 4 and the low reference circuit terminal 11. Verify the scan tool Switch Illumination Dimming parameter displays BRIGHT or DARK.
- If all circuits test normal, test or replace the I/P dimmer switch.
| ⇒ | If the test lamp does not illuminate, test the ground circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the IPC. |
| ⇒ | If not the specified value, test the signal circuit terminal 4 for a short to voltage. If the circuit tests normal, replace the IPC. |
| ⇒ | If not the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the IPC. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for IPC replacement, setup, and programming |
