DTC C0031[08] Front Left Wheel Speed Sensor DMA Buffer Noise Failure (ABS/ESC)

1. Brake control system check

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

2. Prioritized DTC check

1) Turn OFF the ignition switch.

2) Connect the scan tool.

3) Turn ON the ignition switch.

4) Observe the DTC information with a scan tool. Is DTC C0031[01] set at the same time?

Yes

Go to DTC C0031[01] diagnosis.

Refer to "54.Brake Control 4A.Troubleshooting(ABS/ESC) DTC C0031[01] Front Left Wheel Speed Sensor Electrical Failure".

No

=>Go to Front left hub installation status inspection.

3. Front left hub installation status inspection

1) Jack up the vehicle and inspect the hub installation status for the following. Is the result normal?

Inspection items

  • The tire should not be loosened when manually shaken laterally.
  • The hub preload should be the specified value.

Refer to "3.Driveline, Axle 3C.Drive Shaft System front hub installation".

Yes

=>Go to Front left hub disassembly inspection and wheel speed sensor installation status inspection.

No

Repair as necessary.

=>Go to Repair verification.

4. Front left hub disassembly inspection and wheel speed sensor installation status inspection

1) Remove the hub and inspect it for the following. Is the result normal?

Inspection items

  • Hub seal installation status
  • Hub bearing status
  • Hub grease status
  • There should be no looseness of the installed wheel speed sensor.

Refer to "3.Driveline, Axle 3C.Drive Shaft System front hub removal".

Refer to "3.Driveline, Axle 3C.Drive Shaft System front hub inspection".

Refer to "3.Driveline, Axle 3C.Drive Shaft System front hub installation".

Yes

=>Go to Front left wheel speed sensor inspection.

No

Repair as necessary.

=>Go to Repair verification.

5. Front left wheel speed sensor inspection

1) Inspect the wheel speed sensor for the following. Is the result normal?

Inspection items

  • There should be no damage from interference with the exciter ring, etc.
  • There should be no deformation.
  • There should be no adhesion of large amounts of magnetic material, such as iron powder.

Yes

=>Go to Front left exciter ring inspection.

No

Replace the front left wheel speed sensor or remove the magnetic material.

Refer to "4.Brakes 4Z.Brake Electrical Control front wheel speed sensor removal".

Refer to "4.Brakes 4Z.Brake Electrical Control front wheel speed sensor installation".

=>Go to Repair verification.

6. Front left exciter ring inspection

1) Inspect the exciter ring for the following. Is the result normal?

Inspection items

  • There should be no damage from interference with the wheel speed sensor, etc.
  • There should be no deformation or eccentricity.
  • There should be no adhesion of large amounts of magnetic material, such as iron powder.
  • The garter spring should not coil itself around the exciter ring.

Yes

=>Go to Procedure completion check.

No

Replace the exciter ring or remove the magnetic material.

Refer to "4.Brakes 4D.ABS front exciter ring removal".

Refer to "4.Brakes 4D.ABS front exciter ring installation".

Note

  • Because the exciter ring cannot be reused, always install a new one if it is removed.

=>Go to Repair verification.

7. Procedure completion check

1) Securely connect the disconnected harness connectors.

2) Clear the DTC with a scan tool.

3) Turn OFF the ignition switch.

4) Start the engine and drive at 25 km/h {16 mph} or more.

5) Observe the DTC information with a scan tool. Is a DTC set?

Yes

=>Go to EHCU replacement.

No

The system is normal.

8. 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.

9. Repair verification

1) Clear the DTC with a scan tool.

2) Turn OFF the ignition switch.

3) Start the engine and drive at 25 km/h {16 mph} or more.

4) Observe the DTC information with a scan tool.

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