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• | 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. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
F4DR Fuse B+ | 1 | 1 | -- | -- |
F11DL Fuse B+ | 1 | 1 | -- | -- |
Headlamp Main Beam Relay Control | B2580 02, B2580 04 | B2580 02, B2580 04 | B2580 01 | -- |
Dipped Beam Headlamp Control - Left | 1 | 1 | 1 | -- |
Dipped Beam Headlamp Control - Right | 1 | 1 | 1 | -- |
Main Beam Headlamp Control - Left | 2 | 2 | 2 | -- |
Main Beam Headlamp Control - Right | 2 | 2 | 2 | -- |
Indicator/Multifunction Switch Headlamps OFF Signal | B257A 00 | 3 | 3 | -- |
Indicator/Multifunction Switch Headlamps ON Signal | B257A 00 | 3 | 3 | -- |
Indicator/Multifunction Switch Flash To Pass Signal | B3806 00 | 3 | 3 | -- |
Indicator/Multifunction Switch Main Beam Signal | B3650 08 | 3 | 3 | -- |
Headlamp Ground - Left | -- | 1, 2 | -- | -- |
Headlamp Ground - Right | -- | 1, 2 | -- | -- |
Indicator/Multifunction Switch Ground | - | 3 | -- | -- |
1. Headlamps Malfunction - Dipped beam 2. Headlamps Malfunction - Main beam 3. Indicator/Multifunction Switch Malfunction |
For headlamp operation, the body control module (BCM) monitors three signal circuits from the indicator/multifunction switch. When the indicator/multifunction switch is in the AUTO position, the three signal circuits are open and the BCM relies on the ambient light sensor input to turn the headlamps and daytime running lamps (DRL) ON and OFF. When the indicator/multifunction switch is placed in the OFF position, the indicator/multifunction switch headlamps OFF signal circuit is grounded, indicating to the BCM that the exterior lamps should be turned OFF. With the indicator/multifunction switch in the PARK lamps position, the indicator/multifunction switch sidelights ON signal circuit is grounded, indicating that the sidelights have been requested. When the indicator/multifunction switch is in the HEADLAMP position, both the indicator/multifunction switch sidelights ON signal circuit and the indicator/multifunction switch headlamps ON signal circuit are grounded. The BCM responds by commanding the sidelights and headlamps ON.
The main beam and flash to pass functions are contained within the indicator/multifunction switch. The BCM provides the indicator/multifunction switch with two signal circuits, the main beam signal circuit and the flash to pass signal circuit. When the dipped beam headlamps are ON and the indicator/multifunction switch is placed in the main beam position, ground is applied to the BCM through the main beam signal circuit. The BCM responds to the main beam request by applying ground to the main beam relay control circuit which energises the main beam relay. With the main beam relay energised, the switch contacts close allowing battery voltage to flow through the main beam fuses to the main beam control circuits illuminating the main beam headlamps.
When the indicator/multifunction switch is momentarily placed in the flash to pass position, ground is applied to the BCM through the flash to pass signal circuit. The BCM responds by applying ground to the main beam relay control circuit which energises the main beam relay illuminating the main beams for a brief moment or until the flash to pass switch is released.
Exterior Lighting Systems Description and Operation
Control Module References for scan tool information
⇒ | If the parameter does not change between the commanded states, refer to Indicator/Multifunction Switch Malfunction. |
⇒ | If the parameter does not change between the commanded states, refer to Indicator/Multifunction Switch Malfunction. |
⇒ | If the parameter does not change between the commanded states, refer to Indicator/Multifunction Switch Malfunction. |
⇒ | If the parameter does not change between the commanded states, refer to Indicator/Multifunction Switch Malfunction. |
⇒ | If the left dipped beam headlamp does not turn ON and OFF when commanded, refer to Headlamps Malfunction - Dipped Beam. |
⇒ | If the right dipped beam headlamp does not turn ON and OFF when commanded, refer to Headlamps Malfunction - Dipped Beam. |
⇒ | If the main beam headlamps do not turn ON and OFF when commanded, refer to Headlamps Malfunction - Main Beam. |
⇒ | If the main beam indicator does not illuminate or remains illuminated at all times, replace the P16 Instrument Cluster. |
⇒ | If greater then the specified range, test the ground circuit for an open/high resistance. |
⇒ | If not the specified value, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If not the specified value, test the signal circuit terminal 9 for a short to ground. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If not the specified value, test the signal circuit terminal 11 for a short to ground. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If not the specified value, test the signal circuit terminal 12 for a short to ground. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. |
⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the K9 Body Control Module. |
⇒ | If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 Body Control Module. |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the X50A Fuse Block - Under-bonnet. |
⇒ | If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the X50A Fuse Block - Under-bonnet. |
Perform the Diagnostic Repair Verification
• | Control Module References for BCM replacement, programming and setup |
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