DTC C0031[14] Front Left Wheel Speed Sensor Signal Line Failure (Short to GND or Line Open) (ABS/ESC)

1. Brake control system check

Refer to "54.Brake Control 4A.Troubleshooting(ABS/ESC) diagnostic System Check - Brake Controls".

2. Wheel speed sensor wire harness and connector inspection

1) Turn OFF the ignition switch.

2) Disconnect the EHCU harness connector (C13) and front left wheel speed sensor harness connectors (C25).

3) Inspect the wire harnesses and connectors for the following. Is the result normal?

Wire harness to be inspected

  • Between the EHCU (pin 8 of C13) and the front left wheel speed sensor (pin 1 of C25)

Inspection items

  • Continuity
  • Short to ground or short to other circuits
  • Terminal connection status

Refer to "RHD Anti-lock Brake" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "LHD Anti-lock Brake" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Electronic Stability Control" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "LHD Electronic Stability Control" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

=>Go to EHCU replacement.

No

Repair the circuit as necessary.

=>Go to Repair verification.

3. EHCU replacement

Note

  • Perform programming after replacing the EHCU.

Refer to "4.Brakes 4Z.Brake Electrical Control EHCU removal".

Refer to "4.Brakes 4Z.Brake Electrical Control EHCU installation".

Refer to "4.Brakes 4Z.Brake Electrical Control EHCU setting".

Procedure completion

=>Go to Repair verification.

4. Repair verification

1) Clear the DTC with a scan tool.

2) Turn OFF the ignition switch.

3) Turn ON the ignition switch.

4) Observe the DTC information with a scan tool.

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