Toyota Corolla 2004 DIAGNOSTICS – ABS WITH EBD SYSTEM

05–330

–DIAGNOSTICS ABS WITH EBD SYSTEM (April, 2003)

DTC C1251/51 PUMP MOTOR IS LOCKED/OPEN CIRCUIT

IN PUMP MOTOR GROUND

CIRCUIT DESCRIPTION

DTC No. DTC Detecting Condition Trouble Area

C1251/51

WIRING DIAGRAM

ABS actuator pump motor is not operating normally during
initial check.

ABS pump motor

057UL–04

FL MAIN

Battery

Engine Room R/B and J/B

B

1

1A

ALT ABS No.2

1

Skid Control ECU with Actuator

L

24

S1

+BM

1212

W–B

W–B

1

S1

23
S1

GND1

GND2

W–B

EA

2004 COROLLA (RM1037U)

C96169

495Author: Date:

05–331

–DIAGNOSTICS ABS WITH EBD SYSTEM (April, 2003)

INSPECTION PROCEDURE

HINT:
Start the inspection from step 1 in case of using the hand–held tester and start from step 2 in case of not
using hand–held tester.

1 INSPECT BRAKE ACTUATOR ASSY

(a) Select the DATALIST mode on the hand–held tester.
(b) Check the operation sound of the ABS pump motor when operating it with the hand–held tester.

OK:
The operation sound of the ABS pump motor should be heard.

OK PROCEED TO NEXT CIRCUIT INSPECTION

SHOWN ON PROBLEM SYMPTOMS TABLE

NG

2 INSPECT SKID CONTROL ECU TERMINAL VOLTAGE(+BM TERMINAL VOLTAGE)

(a) Disconnect the skid control ECU connector.
(b) Measure the voltage between terminal +BM (24) and

GND (23) of skid control ECU harness side connector.

OK:
The operation sound of the ABS pump motor should
be heard.

GND2

(–)

+BM

(+)

C58919

OK

REPLACE BRAKE ACTUATOR ASSY

NG REPAIR OR REPLACE HARNESS OR

CONNECTOR

2004 COROLLA (RM1037U)

496Author: Date: