DTC C143A-7E: ABS Solenoid Control Actuator Stuck On; DTC C143A-7F: ABS Solenoid Control Actuator Stuck Off [11/2021 - ]: Procedure
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- CHECK HARNESS AND CONNECTOR (+BS TERMINAL)
- Make sure that there is no looseness at the locking part and the connecting part of the connectors.
OK
The connector is securely connected.
- Disconnect the A38 No. 2 skid control ECU (brake actuator assembly) connector.
- Check both the connector case and the terminals for deformation and corrosion.
OK
No deformation or corrosion.
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition A38-14 (+BS) - Body ground Always 11 to 14 V Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 2
- Make sure that there is no looseness at the locking part and the connecting part of the connectors.
- CHECK HARNESS AND CONNECTOR (GND1 TERMINAL)
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition A38-1 (GND1) - Body ground 1 minute or more after disconnecting the cable from the negative (-) auxiliary battery terminal Below 1 Ω Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 3
- Measure the resistance according to the value(s) in the table below.
- CLEAR DTC
- Reconnect the A38 No. 2 skid control ECU (brake actuator assembly) connector.
- Clear the DTCs.
Chassis > Brake/EPB > Clear DTCs
- Turn the ignition switch off.
Result
Proceed to NEXT
Result:
NEXT
See step 4
- RECONFIRM DTC
- Based on the Freeze Frame Data and interview with the customer, attempt to reproduce the conditions when the malfunction occurred.
- Check if the same DTC is output.
Chassis > Brake/EPB > Trouble Codes
HINT:
- If a speed signal of 6 km/h (4 mph) or more is input to the No. 2 skid control ECU (brake actuator assembly) with the ignition switch turned to ON and the stop light switch assembly off, the ECU performs self-diagnosis of the solenoid circuit.
- If the normal system code is output (no DTCs are output), slightly jiggle the connectors, wire harnesses, and fuses of the No. 2 skid control ECU (brake actuator assembly).
- If any DTCs are output while jiggling a connector or wire harness of the No. 2 skid control ECU (brake actuator assembly), inspect and repair the connector or wire harness.
- If no DTCs were output when reconfirming DTCs, checking for intermittent problems is necessary because it is suspected that the original DTCs were stored due to the poor connection of a connector terminal.
Result
Result Proceed to DTCs C143A-7E and C143A-7F are not output. A DTCs C143A-7E and/or C143A-7F are output. B
Result:
A
USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - ]
Result:
B
REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to REMOVAL [11/2021 - ]