DTC    C1251/51    Open in Pump Motor Circuit

for Preparation Click here


DESCRIPTION

The motor relay (semiconductor relay) is housed in the skid control ECU and drives the pump motor based on a signal from the skid control ECU.

DTC No.
DTC Detecting Condition
Trouble Area
C1251/51
  1. Actuator pump motor does not operate properly.
  2. Open in actuator pump motor circuit continues for at least 2 sec.
  1. ABS and TRACTION actuator assembly (GND circuit)
  2. ABS and TRACTION actuator assembly (Motor circuit)

WIRING DIAGRAM

Refer to DTC C0273/13, C0274/14 and C1361/91 (Click here).

INSPECTION PROCEDURE

NOTICE:
When replacing the ABS and TRACTION actuator assembly, perform zero point calibration (Click here).

1.INSPECT SKID CONTROL ECU (GND2 TERMINAL)


    F049362E17

  1. Disconnect the skid control ECU connector.

  1. Measure the resistance according to the value(s) in the table below.

    Resistance:
    Tester Connection
    		Specified Condition
    A48-1 (GND2) - Body ground
    		Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (GND2 CIRCUIT)
OK


2.PERFORM ACTIVE TEST BY INTELLIGENT TESTER (ABS MOTOR RELAY)

  1. Connect the intelligent tester to the DLC3.

  1. Start the engine.

  1. Select the ACTIVE TEST mode on the intelligent tester.

  1. Check the operating sound of the ABS motor relay and motor when operating it with the intelligent tester.

    ACTIVE TEST: ABS/VSC/TR(A)C 
    Item
    		Vehicle Condition / Test Details
    		Diagnostic Note
    Motor Relay
    		Turns ABS motor relay ON or OFF
    		Operating sound of relay (clicking sound) and motor can be heard

    OK:
    The operating sound of the ABS motor relay and motor can be heard.



NG
REPLACE ABS AND TRACTION ACTUATOR ASSEMBLY
OK


3.RECONFIRM DTC

  1. Clear the DTC (Click here).

  1. Start the engine.

  1. Drive the vehicle at the speed of 4.3 mph (7 km/h) or more.

  1. Check that the same DTC is recorded (Click here).

    HINT:
    Reinstall the sensors, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.


    Result:

    Condition
    		Proceed To
    DTC (C1251/51) is not output
    		A
    DTC (C1251/51) is output
    		B

    HINT:
    1. If a speed signal of 4 mph (6 km/h) or more is input to the skid control ECU, with the engine switch on (IG) and the stop light switch off, the ECU performs self diagnosis of the motor and solenoid circuits.
    2. If a normal system code is output (trouble code is not output), slightly jiggle the connectors, wire harness, and fuses of the ABS and TRACTION actuator assembly. Make sure that no DTCs are output.
    3. If any DTCs are output while jiggling a connector or wire harness of the ABS and TRACTION actuator assembly, inspect and repair the connector or wire harness.



B
REPLACE ABS AND TRACTION ACTUATOR ASSEMBLY
A

END