Brake Control Dynamic Control Systems. Dtc C0273 Open In Abs Motor Relay Circuit

Brake. Corolla. Zre142 Aze141

Brake Control Dynamic Control Systems. Corolla. Zre142 Aze141

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

PERFORM ACTIVE TEST USING TECHSTREAM (ABS MOTOR RELAY)

INSPECT ABS NO. 1 FUSE

INSPECT SKID CONTROL ECU (+BM TERMINAL)

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

DTC Code	DTC Detection Condition	Trouble Area
C0273	Either of the following is detected: All of the following conditions continue for 0.1 seconds or more. The IG1 terminal voltage is between 9.5 and 17.2 V. While initial check, or ABS, BA, TR(A)C or VSC is operating. Relay contact remains open when the relay is ON. Both of the following conditions continue for 0.1 seconds or more. The IG1 terminal voltage is less than 9.5 V. Relay contact remains open when the relay is ON.	ABS NO. 1 fuse ABS motor relay circuit Brake actuator assembly (ABS motor relay)
C0274	When the motor relay is OFF, the motor relay remains closed for 4 seconds or more.	ABS motor relay circuit Brake actuator assembly (ABS 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.	ABS NO. 1 fuse ABS motor fail safe relay circuit Brake actuator assembly (ABS motor fail safe relay)

WIRING DIAGRAM

Corolla. Zre142 Aze141.Brake Control Dynamic Control Systems.Anti-Lock Brake System.
Dtc
C0273 Open In Abs Motor Relay Circuit

INSPECTION PROCEDURE

NOTICE:

When replacing the brake actuator assembly, perform zero point calibration (COROLLA_ZRE142 RM000000XHR08KX.html).

HINT:

When C1241 and/or C1417 is output together with C0273, C0274 and/or C1361, inspect and repair the trouble areas indicated by C1241 and/or C1417 first (COROLLA_ZRE142 RM000000XW60EIX.html, or COROLLA_ZRE142 RM00000368W05LX.html).

1.PERFORM ACTIVE TEST USING TECHSTREAM (ABS MOTOR RELAY)

Connect the Techstream to the DLC3.

Start the engine.

Select the Active Test on the Techstream (COROLLA_ZRE142 RM000000XHW0BYX.html).

ABS/VSC/TRAC
Tester Display
Test Part
Control Range
Diagnostic Note
Motor Relay
ABS motor relay
Relay ON/OFF
Operating sound of motor can be heard

ABS/VSC/TRAC
Tester Display	Test Part	Control Range	Diagnostic Note
Motor Relay	ABS motor relay	Relay ON/OFF	Operating sound of motor can be heard

Check for operating sound of the ABS motor relay when operating it using the Techstream.

Result:

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

Go to step 5

A

2.INSPECT ABS NO. 1 FUSE

Turn the ignition switch off.

Remove the ABS NO. 1 fuse from the engine room relay block.

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Condition
Specified Condition
ABS NO. 1 (50 A) fuse
Always
Below 1 Ω

REPLACE ABS NO. 1 FUSE

OK

3.INSPECT SKID CONTROL ECU (+BM TERMINAL)

Install the ABS NO. 1 fuse.

Make sure that there is no looseness at the locking part and the connecting part of the connector.

Disconnect the skid control ECU connector.

Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection
Condition
Specified Condition
A66-24 (+BM) - Body ground
Always
11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR (+BM CIRCUIT)

OK

4.INSPECT SKID CONTROL ECU (GND2 TERMINAL)

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Condition
Specified Condition
A66-13 (GND2) - Body ground
Always
Below 1 Ω

REPAIR OR REPLACE HARNESS OR CONNECTOR (GND2 CIRCUIT)

OK

5.RECONFIRM DTC

HINT:

This code is detected when a problem is identified in the brake actuator assembly.

The ABS motor relay is in the brake actuator assembly.

Therefore, ABS motor relay inspection and motor relay unit inspection cannot be performed. Be sure to check if the DTC is output before replacing the brake actuator assembly.

Turn the ignition switch off.

Reconnect the skid control ECU connector.

Clear the DTCs (COROLLA_ZRE142 RM000000XHV0F2X.html).

Start the engine.

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

Check if the same DTC is recorded (COROLLA_ZRE142 RM000000XHV0F2X.html).

Result:

Result
Proceed to
DTCs (C0273, C0274 and C1361) are not output
A
DTCs (C0273, C0274 and/or C1361) are output
B
HINT:
1. If a speed signal of 6 km/h (4 mph) or more is input to the skid control ECU 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 (no trouble codes are output), slightly jiggle the connectors, wire harness, and fuses of the 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 brake actuator assembly (skid control ECU), inspect and repair the connector or wire harness.
4. It is suspected that the DTCs were output due to a bad connection of the connector terminal.

REPLACE BRAKE ACTUATOR ASSEMBLY (COROLLA_ZRE142 RM000003CZU00MX.html)

CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (COROLLA_ZRE142 RM000000XHP0EKX.html)

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

Tester Connection	Condition	Specified Condition
ABS NO. 1 (50 A) fuse	Always	Below 1 Ω

Result	Proceed to
DTCs (C0273, C0274 and C1361) are not output	A
DTCs (C0273, C0274 and/or C1361) are output	B