Code No.C1266: Motor System
Code No.C1273: Motor Relay Stuck Off
Code No.C1274: Motor Relay Stuck On




caution If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Diagnose the CAN bus lines before the diagnosis codes (Refer to GROUP 54C, CAN bus-line diagnostic flow ).

OPERATION


The ABS-ECU contains the power supply circuit (terminal 34) for the motor. The motor is energized by the motor relay, which is incorporated in the ABS-ECU.

DIAGNOSIS CODE SET CONDITIONS


These diagnosis codes will be set under the cases below.
Code No. C1266
Code No. C1273
Code No. C1274

PROBABLE CAUSES


The most likely causes for these diagnosis codes to set are:

DIAGNOSIS

STEP 1. M.U.T.-III CAN bus diagnostics.


caution Before connecting or disconnecting the M.U.T.-III, turn the ignition switch to the "LOCK" (OFF) position.
(1)Connect M.U.T.-III to the 16-pin diagnosis connector.
(2)Turn the ignition switch to the "ON" position.
(3)Diagnose the CAN bus line.
(4)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is the check result normal?

Go to Step 3.

Repair the CAN bus line (Refer to GROUP 54C, CAN bus line Diagnostic flow ). Then go to Step 2.

STEP 2. Check whether the diagnosis code is reset.


caution Before connecting or disconnecting the M.U.T.-III, turn the ignition switch to the "LOCK" (OFF) position.
(1)Turn the ignition switch to the "ON" position.
(2)Erase the diagnosis code.
(3)Drive the vehicle at 10 km/h or more for 5 seconds or more.
(4)Turn the ignition switch to the "LOCK" (OFF) position.
(5)Turn the ignition switch to the "ON" position.
(6)Check if the diagnosis code is set.
(7)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is code No.C1266 set?

Go to Step 3.

The procedure is complete.

STEP 3. Voltage measurement at ABS-ECU connector A-01.

(1)Disconnect the connector A-01, and connect special tool ABS check harness (MB991952) to the wiring harness-side connector.
note Do not connect special tool ABS check harness (MB991952) to the ABS-ECU.
(2)Turn the ignition switch to the "ON" position.
(3)Measure the voltage between terminal 34 and earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 5.

Go to Step 4.

STEP 4. Check ABS-ECU connector A-01 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Is the check result normal?

An open or short circuit may be present in the motor power supply circuit. Repair the wiring harness between ABS-ECU connector A-01 terminal 34 and fusible link No.22. Then go to Step 8.

Repair or replace the damaged component(s). Then go to Step 8.

STEP 5. Resistance measurement at ABS-ECU connector A-01.

(1)Disconnect the connector A-01, and connect special tool ABS check harness (MB991952) to the wiring harness-side connector.
note Do not connect special tool ABS check harness (MB991952) to the ABS-ECU.
(2)Measure the resistance between terminal 11 and earth.
OK: Continuity(Less than 2 Ω)

Q. Is the check result normal?

Go to Step 7.

Go to Step 6.

STEP 6. Check ABS-ECU connector A-01 for loose, corroded or damaged terminals, or terminals pushed back in the connector.

Q. Is the check result normal?

An open circuit may be present in the earth circuit. Repair the wiring harness between ABS-ECU connector A-01 terminal 11 and the body earth or terminal 33 and the body earth. Then go to Step 8.

Repair or replace the damaged component(s). Then go to Step 8.

STEP 7. Check whether the diagnosis code is reset.


Check again if the diagnosis code is set.
(1)Turn the ignition switch to the "ON" position.
(2)Erase the diagnosis code.
(3)Drive the vehicle at 10 km/h or more for 5 seconds or more.
(4)Turn the ignition switch to the "LOCK" (OFF) position.
(5)Turn the ignition switch to the "ON" position.
(6)Check if the diagnosis code is set.
(7)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is code No.C1266 set?

Replace the hydraulic unit assembly (integrated with ABS-ECU). Then go to Step 8.

It can be assumed that this malfunction is intermittent. Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction .

STEP 8. Check whether the diagnosis code is reset.


Check again if the diagnosis code is set.
(1)Turn the ignition switch to the "ON" position.
(2)Erase the diagnosis code.
(3)Drive the vehicle at 10 km/h or more for 5 seconds or more.
(4)Turn the ignition switch to the "LOCK" (OFF) position.
(5)Turn the ignition switch to the "ON" position.
(6)Check if the diagnosis code is set.
(7)Turn the ignition switch to the "LOCK" (OFF) position.

Q. Is code No.C1266 set?

Go to Step 1.

The procedure is complete.