Headlamp (HI) Circuit

HEADLAMP (HI) CIRCUIT





Description
The IPDM E/R (intelligent power distribution module engine room) controls the headlamp LH high and headlamp RH high relays based on inputs from the BCM via the CAN communication lines. When the headlamp LH high and headlamp RH high relays are energized, power flows through fuses 34 and 35, located in the IPDM
E/R. Power then flows to the front combination lamps to the headlamp high beam.




Component Function Check
1.CHECK HEADLAMP (HI) OPERATION
WITHOUT CONSULT-III
1. Start IPDM E/R auto active test. Diagnosis Description.
2. Check that the headlamp switches to the high beam.

NOTE:
HI/LO is repeated 1 second each when using the IPDM E/R auto active test.
CONSULT-III
1. Select "EXTERNAL LAMPS" of IPDM E/R active test item.
2. With the test item operating, check that the headlamp switches to high beam.





Does the headlamp switch to high beam?
YES - Headlamp (HI) circuit is normal.
NO - SEE Diagnosis Procedure.




Diagnosis Procedure
Regarding Wiring Diagram information, [1][2]Electrical Diagrams.
1.CHECK HEADLAMP (HI) FUSES
1. Turn the ignition switch OFF.
2. Check that the following fuses are not open.





Is the fuse open?
YES - Repair the harness and replace the fuse.
NO - GO TO 2.
2.CHECK HEADLAMP (HI) OUTPUT VOLTAGE





1. Turn the ignition switch OFF.
2. Disconnect the front combination lamp connector.
3. Turn the ignition switch ON.
4. Turn the high beam headlamps ON.
5. With the high beam headlamps ON, check the voltage between the combination lamp connector and ground.










Are the voltage readings as specified?
YES - GO TO 4.
NO - GO TO 3.
3.CHECK HEADLAMP (HI) CIRCUIT FOR OPEN





1. Turn the ignition switch OFF.
2. Disconnect IPDM E/R connector E123.
3. Check continuity between the IPDM E/R harness connector (A) and the front combination lamp harness connector (B).






Does continuity exist?
YES - Replace IPDM E/R. Service and Repair
NO - Repair the harnesses or connectors.
4.CHECK FRONT COMBINATION LAMP (HI) GROUND CIRCUIT





Check continuity between the front combination lamp harness connector terminal and ground.





Does continuity exist?
YES - Inspect the headlamp bulb.
NO (Except LH with DTRL)- Repair the harness.
NO (LH with DTRL)- GO TO 5.
5.CHECK CONTINUITY BETWEEN FRONT COMBINATION LAMP LH (HI) AND DAYTIME LIGHT RELAY
1. Disconnect daytime light relay connector.
2. Check continuity between front combination lamp LH harness connector and daytime light relay harness connector.





Does continuity exist?
YES - GO TO 6.
NO - Repair the harness or connector.
6.CHECK DAYTIME LIGHT RELAY GROUND CIRCUIT
Check continuity between daytime light relay harness connector and ground.





Does continuity exist?
YES - GO TO 7.
NO - Repair the harness or connector.
7.CHECK DAYTIME LIGHT RELAY
Check daytime light relay. SEE Component Inspection
Is the inspection result normal?
YES - Inspect daytime light relay circuit for short. If OK, replace IPDM E/R. Service and Repair
NO - Replace daytime light relay.




Component Inspection
1. CHECK DAYTIME LIGHT RELAY
1. Turn ignition switch OFF.
2. Remove daytime light relay.
3. Check the continuity between daytime light relay terminals under the following conditions.





Is the inspection result normal?
YES - Inspection End.
NO - Replace daytime light relay