Dtc C1257 Power Supply Drive Circuit

Brake. Land Cruiser. Urj200, 202 Grj200 Vdj200
Brake Control Dynamic Control Systems. Land Cruiser. Urj200, 202 Grj200 Vdj200

DESCRIPTION

INSPECTION PROCEDURE

CHECK PUMP MOTOR OPERATION

RECONFIRM DTC

DTC C1257 Power Supply Drive Circuit


DESCRIPTION

The motor relay (semiconductor relay) is built into the master cylinder solenoid and drives the pump motor based on a signal from the skid control ECU (master cylinder solenoid).

DTC Code
DTC Detection Condition
Trouble Area
C1257
There is an open in the motor system circuit (motor input circuit).
Skid control ECU (Master cylinder solenoid)

INSPECTION PROCEDURE

NOTICE:
After replacing the master cylinder solenoid, perform zero point calibration (Click here).
1.CHECK PUMP MOTOR OPERATION

  1. Turn the ignition switch off.

  1. Disconnect the A24 skid control ECU (master cylinder solenoid) connector.

  1. Depress the brake pedal more than 40 times.

  1. Turn the ignition switch to ON.

  1. Check pump motor operation.

    OK:
    Pump motor operates normally.

    Result
    Result
    		Proceed to
    OK
    		A
    NG (for LHD)
    		B
    NG (for RHD)
    		C


B
REPLACE MASTER CYLINDER SOLENOID (Click here)

C
REPLACE MASTER CYLINDER SOLENOID (Click here)
A


2.RECONFIRM DTC

  1. Turn the ignition switch off.

  1. Reconnect the A24 skid control ECU (master cylinder solenoid) connector.

  1. Turn the ignition switch to ON.

  1. Clear the DTCs (Click here).

  1. Turn the ignition switch off.

  1. Check if the same DTC is output (Click here).

    Result
    Result
    		Proceed to
    DTC is not output
    		A
    DTC is output (for LHD)
    		B
    DTC is output (for RHD)
    		C



B
REPLACE MASTER CYLINDER SOLENOID (Click here)

C
REPLACE MASTER CYLINDER SOLENOID (Click here)
A

CHECK FOR INTERMITTENT PROBLEMS (Click here)