Back-Up Light Circuit

LIGHTING (EXT): LIGHTING SYSTEM: Back-up Light Circuit
- Back-up Light Circuit

DESCRIPTION

The power management control ECU controls the back-up lights via the engine room junction block assembly.

WIRING DIAGRAM





INSPECTION PROCEDURE

NOTICE:
Inspect the fuses and bulbs for circuits related to this system before performing the following inspection procedure.

PROCEDURE

1. CHECK DTC OUTPUT (HYBRID CONTROL SYSTEM)

(a) Check for DTCs Hybrid Control System.

OK:

Hybrid Control System DTCs are not output.

NG -- GO TO HYBRID CONTROL SYSTEM How To Proceed With Troubleshooting
OK -- Continue to next step.

2. CHECK ENGINE ROOM JUNCTION BLOCK ASSEMBLY

(a) Using a voltmeter, check the signal reading of the engine room junction block assembly Testing and Inspection

OK:

Output signal reading is normal.

NG -- INSPECT ENGINE ROOM JUNCTION BLOCK ASSEMBLY (RESULTS OF SIGNAL READING CHECK) Removal
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (ENGINE ROOM JUNCTION BLOCK ASSEMBLY POWER SOURCE AND BODY GROUND) Daytime Running Light Relay Circuit

NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (REAR LIGHT ASSEMBLY - ENGINE ROOM JUNCTION BLOCK ASSEMBLY)

(a) Disconnect the T18 rear light assembly LH connector and T17 rear light assembly RH connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

LH Side





RH Side





NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.

5. CHECK HARNESS AND CONNECTOR (POWER MANAGEMENT CONTROL ECU - ENGINE ROOM JUNCTION BLOCK ASSEMBLY)

(a) Disconnect the A38 power management control ECU connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





NG -- REPAIR OR REPLACE HARNESS AND CONNECTOR
OK -- Continue to next step.

6. CHECK ENGINE ROOM JUNCTION BLOCK ASSEMBLY

(a) Replace the engine room junction block assembly with a new or a known good one Removal.

OK:

The back-up lights operate normally.

NG -- REPLACE POWER MANAGEMENT CONTROL ECU Removal

OK -- END (ENGINE ROOM JUNCTION BLOCK ASSEMBLY WAS DEFECTIVE)