C0273
BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM (for 2ZR-FE): C0273,C0274,C1361: Open in ABS Motor Relay Circuit
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.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
When replacing the brake actuator assembly, perform zero point calibration Programming and Relearning.
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 C1241, or C1417).
PROCEDURE
1. PERFORM ACTIVE TEST USING TECHSTREAM (ABS MOTOR RELAY)
(a) Connect the Techstream to the DLC3.
(b) Start the engine.
(c) Select the Active Test mode on the Techstream Data List / Active Test.
ABS / VSC / TRAC
(d) Check for operating sound of the ABS motor relay when operating it with Techstream.
Result:
B -- RECONFIRM DTC
A -- Continue to next step.
2. INSPECT ABS NO. 1 FUSE
(a) Turn the ignition switch off.
(b) Remove the fusible link block from the engine room relay block.
(c) Check if the fusible link is melted.
OK:
The fusible link is not melted.
(d) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPLACE ABS NO. 1 FUSE
OK -- Continue to next step.
3. INSPECT SKID CONTROL ECU (+BM TERMINAL)
(a) Install the fusible link block to the engine room relay block with the nut.
(b) Make sure that there is no looseness at the locking part and the connecting part of the connectors.
(c) Disconnect the skid control ECU connector.
(d) Measure the voltage according to the value(s) in the table below.
Standard voltage:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (+BM CIRCUIT)
OK -- Continue to next step.
4. INSPECT SKID CONTROL ECU (GND2 TERMINAL)
(a) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (GND2 CIRCUIT)
OK -- Continue to next step.
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.
(a) Turn the ignition switch off.
(b) Reconnect the skid control ECU connector.
(c) Clear the DTCs Reading and Clearing Diagnostic Trouble Codes.
(d) Start the engine.
(e) Drive the vehicle at 20 km/h (12 mph) or more for 30 seconds or more.
(f) Check if the same DTC is output Reading and Clearing Diagnostic Trouble Codes.
Result:
HINT
* 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.
* 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.
* 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.
* It is suspected that the DTCs were output due to a bad connection of the connector terminal.
B -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal
A -- CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) Check for Intermittent Problems