Daytime Running Lamp Relay: Testing and Inspection

Daytime Light Relay Circuit Check

Description

The BCM sends a daytime light request to the IPDM E/R via the CAN communication lines. The power flows backward through fuse 45 located in IPDM E/R to daytime light relay 1 and LH high beam lamp to IPDM E/R, through the high beam fuses, through the RH high beam lamp and on to ground. The high beam lamps are wired in series which causes them to illuminate at a reduced intensity.

Diagnosis Procedure

Regarding Wiring Diagram information, refer to [Daytime Light System: Wiring Diagram] [1][2]Daytime Running Lamp.

1. CHECK DAYTIME LIGHT RELAY 1 FUSE

1 Turn the ignition switch OFF.
2 Check that the following fuse is not open.






Is the fuse open?
YES
Replace the fuse after repairing the affected circuit.
NO
GO TO 2

2. CHECK IPDM E/R OUTPUT SIGNAL

1 Turn the ignition switch OFF.
2 Disconnect the daytime light relay 1 connector.
3 Turn the ignition switch ON.
4 Check the voltage between the daytime light relay 1 harness connector and ground.






Is battery voltage present?
YES
GO TO 3
NO
GO TO 5

3. CHECK DAYTIME LIGHT RELAY 1 CIRCUIT

1 Turn the ignition switch OFF.
2 Disconnect IPDM E/R connector E122.
3 Check continuity between the IPDM E/R harness connector and the daytime light relay 1 harness connector.






4 Check continuity between the daytime light relay 1 harness connector and ground.






Is the measurement value normal?
YES
GO TO 4
NO
Repair the harnesses or connectors.

4. CHECK DAYTIME LIGHT RELAY 1

Check daytime light relay 1. Refer to "Component Inspection".

Is the inspection result normal?
YES
Check headlamp (HI) circuit. If OK, replace IPDM E/R. Refer to [IPDM E/R: Removal and Installation of IPDM E/R] Service and Repair. If NG, refer to [Headlamp (HI) Circuit Check] Headlamp (HI) Circuit Check.
NO
Replace daytime light relay1.

5. CHECK DAYTIME LIGHT RELAY CIRCUIT FOR OPEN

1 Turn the ignition switch OFF.
2 Disconnect IPDM E/R connector E119.
3 Check continuity between the IPDM E/R harness connector and the daytime light relay 1 harness connector.






Does continuity exist?
YES
Replace IPDM E/R. Refer to [IPDM E/R: Removal and Installation of IPDM E/R] Service and Repair.
NO
Repair the harnesses or connectors.

Component Inspection

1. CHECK DAYTIME LIGHT RELAY 1

1 Turn ignition switch OFF.
2 Remove daytime light relay 1.
3 Check the continuity between daytime light relay 1 terminals under the following conditions.






Is the inspection result normal?
YES
Inspection End.
NO
Replace daytime light relay 1