Inspection Procedure
NOTE:
When replacing the skid control ECU, perform initialization of linear solenoid valve and calibration (see INITIALIZATION
).
- CHECK BRAKE CONTROL POWER SUPPLY (IG VOLTAGE)
- Measure the voltage of the connector.
HINT:
Measure the voltage from behind the connector with the connector connected to the skid control ECU.
Standard voltage
TESTER CONNECTION SPECIFIED CONDITIONTester Connection Condition Specified Condition B18-5 (IG) - Body ground Power switch ON (READY) 10 to 14 V
NG : REPAIR OR REPLACE HARNESS AND CONNECTOR
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OK : GO TO NEXT STEP
- Measure the voltage of the connector.
- CHECK WIRE HARNESS (SKID CONTROL ECU - BRAKE CONTROL POWER SUPPLY)
- Disconnect the S8 ECU connector.
- Disconnect the B18 supply connector.
- Measure the resistance of the wire harness side connectors.
Standard resistance
TESTER CONNECTION SPECIFIED CONDITIONTester Connection Specified Condition S8-30 (ENA) - B18-12 (ENA) Below 1 Ω S8-20 (FAIL) - B18-13 (FAIL) Below 1 Ω S8-30 (ENA) - Body ground 10 kΩ or higher S8-20 (FAIL) - Body ground 10 kΩ or higher
NG : REPAIR OR REPLACE HARNESS AND CONNECTOR
OK : GO TO NEXT STEP
- CHECK SKID CONTROL ECU (ENA, FAIL VOLTAGE)
- Using an oscilloscope, check the waveform of the skid control ECU.
OK : Waveform is output as shown in the illustration. Waveform (FAIL)
WAVEFORM REFERENCE (FAIL)Item Content Symbols (terminal No.) S8-20 (FAIL) - S8-1, 2 (GND3, 2) Tool Setting 5 V/DIV/., 200 ms/DIV. Condition Condition READY is displayed on the meter Waveform (ENA)
WAVEFORM REFERENCE (ENA)Item Content Symbols (terminal No.) S8-30 (ENA) - S8-1, 2 (GND3, 2) Tool Setting 5 V/DIV/., 100 ms/DIV. Condition Condition READY is displayed on the meter Result
RESULT REFERENCEResult Proceed to A Both waveforms are normal B Waveform (ENA) is abnormal C Waveform (FAIL) is abnormal
B : REPLACE BRAKE CONTROL POWER SUPPLY
C : REPLACE SKID CONTROL ECU
A : REPLACE SKID CONTROL ECU
- Using an oscilloscope, check the waveform of the skid control ECU.