Headlight ECU LH Communication Stop Mode [10/2018 - ]: Procedure
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- CHECK FOR OPEN IN CAN BUS LINES (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH BRANCH LINE)
- Disconnect the cable from the negative (-) auxiliary battery terminal.
- Disconnect the no. 1 headlight ECU sub-assembly LH connector.
- Measure the resistance according to the value(s) in the table below.
*a Front view of wire harness connector
(to No. 1 Headlight ECU Sub-assembly LH)Standard Resistance
Tester Connection Condition Specified Condition A15-24 (CANH) - A15-23 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE CAN BRANCH LINES OR CONNECTOR (NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH)
Result:
OK
See step 2
- CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)
- Measure the resistance according to the value(s) in the table below.
*a Front view of wire harness connector
(to No. 1 Headlight ECU Sub-assembly LH)Standard Resistance
Tester Connection Condition Specified Condition A15-12 (GND) - Body ground Cable disconnected from negative (-) auxiliary battery terminal Below 1 Ω - Reconnect the cable to the negative (-) auxiliary battery terminal.
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Switch Condition Specified Condition A15-4 (IG) - Body ground Power switch on (IG) 11 to 14 V A15-13 (ECUB) - Body ground Power switch on (IG) 11 to 14 V Result
Proceed to OK NG
Result:
OK
REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH. Refer to REMOVAL [10/2018 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
- Measure the resistance according to the value(s) in the table below.