Skid Control ECU Communication Stop Mode [10/2018 - ]: Procedure
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- CHECK FOR OPEN IN CAN BUS LINES (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY BRANCH LINE)
- Disconnect the cable from the negative (-) auxiliary battery terminal.
- Disconnect the brake booster with master cylinder assembly connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition A37-43 (CA1H) - A37-42 (CA1L) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω A37-30 (CA2H) - A37-29 (CA2L) Cable disconnected from negative (-) auxiliary battery terminal 54 to 69 Ω *a Front view of wire harness connector
(to Brake Booster with Master Cylinder Assembly)Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE CAN BRANCH LINES OR CONNECTOR (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY)
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 A37-26 (GND1) - Body ground Cable disconnected from negative (-) auxiliary battery terminal Below 1 Ω A37-39 (GND2) - Body ground Cable disconnected from negative (-) auxiliary battery terminal Below 1 Ω *a Front view of wire harness connector
(to Brake Booster with Master Cylinder Assembly) - 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 A37-5 (+BI2) - Body ground Power switch off 11 to 14 V A37-15 (+BI1) - Body ground Power switch off 11 to 14 V A37-9 (IG2) - Body ground Power switch on (IG) 11 to 14 V A37-23 (IG1) - Body ground Power switch on (IG) 11 to 14 V Result
Proceed to OK NG
Result:
OK
REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY. Refer to REMOVAL [10/2018 - 07/2022] , or refer to REMOVAL [07/2022 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)
- Measure the resistance according to the value(s) in the table below.