Headlight ECU RH Communication Stop Mode [06/2018 - 07/2019]: Procedure
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- CHECK FOR OPEN IN CAN BUS LINES (HEADLIGHT ECU SUB-ASSEMBLY RH BRANCH LINE)
- Disconnect the cable from the negative (-) auxiliary battery terminal.
- Disconnect the A12 headlight ECU sub-assembly RH connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition A12-24 (CANH) - A12-23 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω *a Front view of wire harness connector
(to Headlight ECU Sub-assembly RH)Result
Result OK NG
Result:
NG
REPAIR OR REPLACE CAN BRANCH LINES OR CONNECTOR (HEADLIGHT ECU SUB-ASSEMBLY RH)
Result:
OK
See step 2
- CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition A12-12 (GND) - Body ground Cable disconnected from negative (-) auxiliary battery terminal Below 1 Ω *a Front view of wire harness connector
(to Headlight ECU Sub-assembly RH) - 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 Condition Specified Condition A12-4 (IG) - Body ground Power switch on (IG) 11 to 14 V Result
Result OK NG
Result:
OK
REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH. Refer to REMOVAL [06/2018 - 09/2022]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
- Measure the resistance according to the value(s) in the table below.