Page 91 of 4500
NG: CHECK FOR SHORT IN ALL HARNESS AND CONNECTOR CONNECTED TO FUSE
AND REPLACE FUSE
OK: Go to next step
3.CHECK TERMINAL VOLTAGE (ABS MOTOR RELAY 5 TERMINAL OF ENGINE ROOM
NO.3 R/B)
a. Remove the ABS MTR relay from the engine room No.3 R/B.
b. Turn the ignition switch to the ON position.
c. Measure the voltage according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
Fig. 65: Identifying ABS MTR Relay Location
Tester ConnectionSpecified Condition
Terminals 5 - Body ground10 to 14V
Page 97 of 4500
Fig. 69: Identifying Skid Control ECU Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
The ABS solenoid relay is built in the ABS & TRACTION Actuator assy. This relay supplies power to each
ABS solenoid. If the initial check is OK, after the ignition switch is turned to the ON position, the relay stays
on.
Fig. 70: DTC C0278/11 And DTC C0279/12 Detecting Condition And Trouble Area
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
WIRING DIAGRAM
Page 101 of 4500
Fig. 73: Identifying SKID Control ECU Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
3.RECONFIRM DTC
HINT:
This code is detected when a problem is determined in the brake actuator assy. The ABS solenoid circuit
is in the brake actuator assy. Therefore, solenoid circuit inspection relay unit inspection cannot be
performed. Be sure to check if the DTC code is output before replacing the brake actuator assy.
a. Clear the DTC (see DTC CHECK/CLEAR
).
b. Turn the ignition switch to the ON position.
c. Check that the same DTC is recorded.
OK: Go to next step
The same DTC is recorded.
NG: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE
Page 104 of 4500

INSPECTION PROCEDURE
HINT:
<003a004b00480051000300380013001400150016001200190015000f0003003800130014001500170012001c001800030052005500030038001300140015001900120019001600030044005500480003005200580057005300580057000300440046004600
520050005300440051004c004800470003005a004c0057004b[ C1210/36 or C1336/39, inspect and
repair the trouble areas indicated by U0123/62, U0124/95 or U0126/63 first.
1.PERFORM ZERO POINT CALIBRATION OF YAW RATE SENSOR AND DECELERATION
SENSOR
a. Perform the zero point calibration of the yaw rate sensor and deceleration sensor (see
CALIBRATION
).
NEXT
2.RECONFIRM DTC
a. Clear the DTCs.
b. Turn the ignition switch to the ON position.
c. Check that the same DTCs are recorded (see DTC CHECK/CLEAR
).
OK: Go to next step
The same DTCs are recorded.
NG: END
HINT:
The DTCs are recorded because zero point calibration has not been completed.
End the procedure since the same DTCs are not recorded after completion of the zero point calibration.
OK: Go to next step
3.CHECK SENSOR INSTALLATION
Check that the yaw rate and deceleration sensor has been installed properly (see
REPLACEMENT
).
OK:
The sensor is tightened to the specified torque.
The sensor is not tilted.
NG: INSTALL YAW RATE SENSOR CORRECTLY
OK: REPLACE YAW RATE SENSOR (SEE REPLACEMENT
)
Page 105 of 4500

HINT:
This DTC is output when the VSC system detects a malfunction in the ABS system.
When DTC C1223/43 is memorized, there is no malfunction in the skid control ECU.
CIRCUIT DESCRIPTION
DTC DETECTING CONDITION DESCRIPTION
INSPECTION PROCEDURE
1.CHECK DTC (FOR ABS SYSTEM)
a. Clear the DTC (see DTC CHECK/CLEAR
).
b. Turn the ignition switch to the ON position.
c. Check that the same DTC is recorded (see DTC CHECK/CLEAR
).
OK: Go to next step
The same DTC is recorded.
NG: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE
HINT:
It is suspect that the DTCs output was caused by the poor connection of the connector terminal.
OK REPAIR CIRCUIT INDICATED BY OUTPUT DTC
CIRCUIT DESCRIPTION
The steering angle sensor signal is sent to the skid control ECU through the CAN communication system. When
there is a malfunction in the communication, it will be detected by the diagnosis function.
DTC No.DTC Detecting ConditionTrouble Area
C1223/43Malfunction in ABS control systemABS control system
Page 109 of 4500
NG: Go to step 3
OK: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
3.CHECK TERMINAL VOLTAGE (STEERING ANGLE SENSOR CONNECTOR)
a. Remove the steering wheel and the column lower cover.
b. Disconnect the steering angle sensor connector.
c. Turn the ignition switch to the ON position.
d. Measure the voltage according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
e. Measure the voltage according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
Tester ConnectionSpecified Condition
S16-1 (IG1) - S16-2 (ESS)10 to 14V
Tester ConnectionSpecified Condition
S16-3 (BAT) -S16-2 (ESS)10 to 14V
Page 113 of 4500
When U0123/62, U0124/95 or U0126/63 are output together with C1232/32, C1234/34, C1243/43, C1244/44,
C1245/45, and C1381/97 inspect and repair the trouble areas indicated by U0121/94, U0123/62, U0124/95 or
U0126/63 first.
1.CHECK SENSOR INSTALLATION (YAW RATE SENSOR)
a. Check that the yaw rate and deceleration sensor has been installed properly (see
REPLACEMENT
).
OK: Go to next step
The sensor is tightened to the specified torque.
The sensor is not tilted.
NG: INSTALL YAW RATE SENSOR CORRECTLY
OK: Go to next step
2.CHECK HARNESS AND CONNECTOR (IG TERMINAL)
a. Disconnect the yaw rate and deceleration sensor connector.
b. Turn the ignition switch to the ON position.
c. Measure the voltage according to the value (s) in the table below.
Standard:
Page 119 of 4500
Fig. 85: Normal Signal Waveform
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: Go to step 4
OK: Go to next step
2.INSPECT SPEED SENSOR AND SENSOR ROTOR SERRATIONS
INSPECTION USING OSCILLOSCOPE
a. Connect the oscilloscope to terminal FR+ - FR- or FL+ - FL- of the skid control ECU.
b. Check if the oscilloscope has any change when the wire harness connector is subject to vibration
while the vehicle is stopped and the ignition switch is on.
(If the connector is poorly connected, vibration of the wire harness connector may cause a temporary stop
in current flow.)
OK: Go to next step
There is no change in a waveform