Dtc C0273 Open In Abs Motor Relay Circuit


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

PERFORM ACTIVE TEST USING INTELLIGENT TESTER (MOTOR RELAY)

CHECK TERMINAL VOLTAGE (BM)

CHECK HARNESS AND CONNECTOR (GND2 TERMINAL)

RECONFIRM DTC

DTC C0273 Open in ABS Motor Relay Circuit

DTC C0274 Short in ABS Motor Relay Circuit

DTC C1361 Short in ABS Motor Fail Safe Relay Circuit


DESCRIPTION

The motor relay supplies power to the pump motor. While the ABS is activated, the ECU turns the motor relay on and operates the pump motor.
If the voltage supplied to the motor relay (BM) is below the DTC detection threshold due to low voltage from the battery or generator, these DTCs may be stored.

DTC Code
DTC Detection Condition
Trouble Area
C0273
Either condition is met:
  1. All conditions are met for 0.12 seconds or more.
    1. The IG1 terminal voltage is between 9.5 and 17.2 V.
    2. During initial check and ABS or BA is operating.
    3. The relay contact is open when the relay is on.
  2. Both conditions are met for 0.12 seconds.
    1. The IG1 terminal voltage is below 9.5 V.
    2. The relay contact remains open when the relay is on.
  1. ABS NO. 1 fuse
  2. Motor relay circuit
  3. Brake actuator assembly (Motor relay)
C0274
When the motor relay is off, the motor relay remains closed for 4 seconds or more.
  1. Motor relay circuit
  2. Brake actuator assembly (Motor relay)
C1361
Immediately after the ignition switch is turned to ON, the relay contact is closed for 4 seconds when the motor fail-safe relay is off.
  1. ABS NO. 1 fuse
  2. Motor fail-safe relay circuit
  3. Brake actuator assembly (Motor fail-safe relay)

WIRING DIAGRAM


Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Brake Control Dynamic Control Systems.Anti-Lock Brake System. Dtc C0273 Open In Abs Motor Relay Circuit


INSPECTION PROCEDURE

NOTICE:
  1. When replacing the skid control ECU (brake actuator assembly), perform calibration (LandCruiser RM000000XHR0BJX.html).
  2. Inspect the fuses for circuits related to this system before performing the following inspection procedure.
HINT:
When DTC C1241 is output together with DTC C0273, C0274 and/or C1361, inspect and repair the trouble areas indicated by DTC C1241 first (LandCruiser RM000000XW60J5X.html).
1.PERFORM ACTIVE TEST USING INTELLIGENT TESTER (MOTOR RELAY)

  1. Turn the ignition switch off.

  1. Connect the intelligent tester to the DLC3.

  1. Start the engine.

  1. Turn the intelligent tester on.

  1. Enter the following menus: Chassis / ABS/VSC/TRC / Active Test.

    ABS/VSC/TRC
    Tester Display
    		Test Part
    		Control Range
    		Diagnostic Note
    Motor Relay
    		Motor relay
    		Relay ON / OFF
    		The operating sound of the motor can be heard.

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

    Result
    Result
    		Proceed to
    Operating sound is not heard
    		A
    Operating sound is heard
    		B


B
Go to step 4
A


2.CHECK TERMINAL VOLTAGE (BM)

  1. Turn the ignition switch off.

  1. Disconnect the A6 skid control ECU (brake actuator assembly) connector.



    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Brake Control Dynamic Control Systems.Anti-Lock Brake System. Dtc C0273 Open In Abs Motor Relay Circuit

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    A6-24 (BM) - Body ground
    		Always
    		11 to 14 V
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Skid Control ECU [Brake Actuator Assembly])


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.CHECK HARNESS AND CONNECTOR (GND2 TERMINAL)

  1. Disconnect the A6 skid control ECU (brake actuator assembly) connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A6-13 (GND2) - Body ground
    		Always
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


4.RECONFIRM DTC
HINT:
This code is stored when a problem is identified in the skid control ECU (brake actuator assembly).
The motor relay is in the skid control ECU (brake actuator assembly).
Therefore, motor relay inspections and motor relay unit inspections cannot be performed. Be sure to check if the DTC is output before replacing the skid control ECU (brake actuator assembly).

  1. Turn the ignition switch off.

  1. Reconnect the skid control ECU (brake actuator assembly) connector.

  1. Clear the DTCs (LandCruiser RM000000XHV0KDX.html).

  1. Start the engine.

  1. Drive the vehicle at a speed of 20 km/h (12 mph) or more for 30 seconds or more.

  1. Check if the same DTC is output (LandCruiser RM000000XHV0KDX.html).

    Result
    Result
    		Proceed to
    DTC not output
    		A
    DTC output
    		B
    HINT:
    1. If a speed signal of 6 km/h (4 mph) or more is input to the skid control ECU (brake actuator assembly) with the ignition switch ON and the stop light switch off, the ECU performs self-diagnosis of the motor and solenoid circuits.
    2. If the normal system code is output (the trouble code is not output), slightly jiggle the connectors, wire harnesses, and fuses of the skid control ECU (brake actuator assembly). Make sure that no DTCs are output.
    3. If any DTCs are output while jiggling a connector or wire harness of the skid control ECU (brake actuator assembly), inspect and repair the connector or wire harness. The DTCs were probably output due to a bad connection of the connector terminal.


B
REPLACE BRAKE ACTUATOR ASSEMBLY (LandCruiser RM0000034UX02TX.html)
A

USE SIMULATION METHOD TO CHECK (LandCruiser RM000003YMJ00XX.html)