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. |
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
B+ -- Dome Lamp | 1 | 1 | -- | -- |
Dome Lamp Control | 2 | 1 | 1 | -- |
Ground -- Dome Lamp | -- | 1 | 1 | -- |
1. Dome Lamp Always OFF 2. Dome Lamp Always ON | ||||
Circuit/System Description
The dome lamp can be turned ON and OFF by opening and closing the door or by turning the dome lamp switch ON and OFF.
Battery voltage is supplied at all times to the dome lamp from circuit breaker 7 located in I/P-1 fuse block. When the door is opened, ground from the door jamb switch is applied through the control circuit and the dome lamp diode to the dome lamp. The dome lamp will remain illuminated until the door is closed.
With the door closed, the dome lamp can also be turned ON and OFF by using the dome lamp switch. Ground for the dome lamp is provided at G400.
Reference Information
Schematic Reference
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 Verification
- Doors closed, press the dome lamp switch ON and OFF. The dome lamp should turn ON and OFF when changing between the commanded states
- Verify that the dome lamp illuminates when the door is OPENED.
| ⇒ | If the dome lamp does not turn ON or is always ON, refer to the Dome Lamp Test. |
| ⇒ | If the dome lamp does not illuminate, refer to the Door Jamb Switch Test. |
Circuit/System Testing
Dome Lamp Test
- Ignition OFF, disconnect the harness connector at the dome lamp.
- Test for less than 5.0 ohms between ground circuit terminal A and ground.
- With the door CLOSED, test for infinite resistance between ground circuit terminal B and ground.
- Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal C and ground.
- If all circuits test normal, test or replace the dome lamp bulb or the dome lamp.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
| ⇒ | If not the specified value, test the ground circuit for a short to ground. If the circuit tests normal, test or replace the door jamb switch. |
| ⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or open/high resistance. |
Door Jamb Switch Test
- Ignition OFF, disconnect the harness connector at the door jamb switch.
- Connect a 3A fused jumper wire between the control circuit terminal A and ground. The dome lamp should illuminate.
- If all circuits test normal, test or replace the dome lamp switch.
| ⇒ | If the dome lamp does not illuminate, test the control circuit for an open/high resistance. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
