DTC C052B[1F] Pump Motor Supply Voltage Line Test Failure (ABS/ESC)

1. Brake control system check

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

2. Current DTC check

1) Turn OFF the ignition switch.

2) Connect the scan tool.

3) Start the engine and drive at 15 km/h {9.3 mph} or more.

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

Yes

=>Go to Inspect the EHCU power supply circuit and ground circuit..

No

Go to Intermittent conditions of brake.

Refer to "205.Brakes 18D.Symptom intermittent conditions of brake".

3. Inspect the EHCU power supply circuit and ground circuit.

1) Turn OFF the ignition switch.

2) Disconnect the EHCU harness connector (C13).

3) Inspect the wire harness for the following. Is the result normal?

Wire harness to be inspected

  • Between the ABS1⋅ESC1 50A fuse and the EHCU (pins 1 of C13)
  • Between the DCDC2/ABS2⋅ESC2 30A fuse and the EHCU (pin 25 of C13)
  • Between the ABS 10A fuse and the EHCU (pin 28 of C13)
  • Between the EHCU (pins 13 and 38 of C13) and the body ground

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 harness connector inspection.

No

Repair the cause for low voltage on the vehicle side as necessary.

=>Go to Repair verification.

4. EHCU harness connector inspection

1) Inspect the connection status of the EHCU harness connector terminals (pins 1, 13, 25, 28, and 38 of C13). Is the connection status normal?

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 connections as necessary.

=>Go to Repair verification.

5. 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.

6. Repair verification

1) Clear the DTC with a scan tool.

2) Turn OFF the ignition switch.

3) Operate under the conditions for setting the DTC.

4) Observe the DTC information with a scan tool.

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