Mazda 6. Manual - part 250

P–56

ON-BOARD DIAGNOSTIC (ABS/TCS) 

End Of Sie

DTC C1145, C1155, C1165, C1175

A6E697567650W10

Caution

• When attaching the tester lead to the ABS (ABS/TCS) HU/CM harness connector, the SST (49 G066 

001) must be used. (See 

P–29 ABS (ABS/TCS) HU/CM INSPECTION

.)

DTC

C1145
C1155
C1165
C1175

RF wheel-speed sensor
LF wheel-speed sensor
RR wheel-speed sensor
LR wheel-speed sensor

DETECTION 

CONDITION

• Abnormal input is detected.

POSSIBLE 

CAUSE

• Open or short to ground circuit in harness between ABS (ABS/TCS) HU/CM terminal and wheel-speed 

sensor(s) terminal below
— ABS (ABS/TCS) HU/CM terminal G—RF ABS wheel-speed sensor terminal A
— ABS (ABS/TCS) HU/CM terminal D—RF ABS wheel-speed sensor terminal B
— ABS (ABS/TCS) HU/CM terminal I—LF ABS wheel-speed sensor terminal A
— ABS (ABS/TCS) HU/CM terminal E—LF ABS wheel-speed sensor terminal B
— ABS (ABS/TCS) HU/CM terminal A—RR ABS wheel-speed sensor terminal A
— ABS (ABS/TCS) HU/CM terminal B—RR ABS wheel-speed sensor terminal B
— ABS (ABS/TCS) HU/CM terminal C—LR ABS wheel-speed sensor terminal A
— ABS (ABS/TCS) HU/CM terminal F—LR ABS wheel-speed sensor terminal B

• ABS wheel-speed sensor(s) malfunction

ON-BOARD DIAGNOSTIC (ABS/TCS) 

P–57

P

P–58

ON-BOARD DIAGNOSTIC (ABS/TCS) 

Diagnostic procedure

End Of Sie

STEP

INSPECTION

ACTION

1

INSPECT WHEEL-SPEED SENSOR CIRCUIT 
FOR OPEN CIRCUIT

• Turn ignition key to OFF.

• Disconnect ABS (ABS/TCS) HU/CM 

connector.

• Measure resistance between suspected 

sensor terminals of ABS (ABS/TCS) HU/CM 
connector (harness side).
— RF wheel-speed sensor: G—D
— LF wheel-speed sensor: I—E
— RR wheel-speed sensor: A—B
— LR wheel-speed sensor: C—F

• Is resistance within 1.3—1.7 kilohm?

Yes

Go to next step.

No

Go to Step 3.

2

INSPECT WHEEL-SPEED SENSOR CIRCUIT 
FOR SHORT TO GROUND

• Turn ignition key to OFF.

• Inspect continuity between suspected sensor 

terminal(s) of ABS (ABS/TCS) HU/CM 
connector (harness side) and ground(s).
— RF wheel-speed sensor: G—D
— LF wheel-speed sensor: I—E
— RR wheel-speed sensor: A—B
— LR wheel-speed sensor: C—F

• Is there continuity?

Yes

Repair or replace harness for short to ground circuit 
between ABS (ABS/TCS) HU/CM and wheel-speed 
sensor(s), then go to Step 5.

No

Go to Step 5.

3

INSPECT WHEEL-SPEED SENSOR

• Turn ignition key to OFF.

• Disconnect suspected sensor connector(s) 

and inspect resistance between sensor 
terminals (part side).

• Is resistance within 1.3—1.7 kilohm?

Yes

Go to next step.

No

Replace wheel-speed sensor, then go to Step 5.

4

INSPECT ABS (ABS/TCS) HU/CM TO 
WHEEL-SPEED SENSOR CIRCUIT FOR 
OPEN CIRCUIT

• Inspect continuity between suspected sensor 

terminal(s) of ABS (ABS/TCS) HU/CM 
connector (harness side) and wheel-speed 
sensor connector. (vehicle harness side)
— RF wheel-speed sensor (+): G—A
— RF wheel-speed sensor (–): D—B
— LF wheel-speed sensor (+): I—A
— LF wheel-speed sensor (–): E—B
— RR wheel-speed sensor (+): A—A
— RR wheel-speed sensor (–): B—B
— LR wheel-speed sensor (+): C—A
— LR wheel-speed sensor (–): F—B

• Is there continuity?

Yes

Repair or replace poor connections of ABS (ABS/TCS) HU/
CM connector and/or wheel-speed sensor connector(s), 
then go to next step.

No

Repair or replace harness for open circuits between ABS 
(ABS/TCS) HU/CM and wheel-speed sensor(s), then go to 
next step.

5

VERIFY TROUBLESHOOTING COMPLETED

• Make sure to reconnect all disconnected 

connectors.

• Clear DTC from memory

(See 

P–46 Clearing DTCs Procedures

)

• Is same DTC present?

Yes

Replace ABS (ABS/TCS) HU/CM, then go to next step.

No

Go to next step.

6

VERIFY AFTER REPAIR PROCEDURE

• Is there any other DTC present?

Yes

Go to applicable DTC inspection.

No

Troubleshooting completed.

ON-BOARD DIAGNOSTIC (ABS/TCS) 

P–59

P

DTC C1148, C1158, C1168, C1178, C1233, C1234, C1235, C1236

A6E697567650W11

Caution

• When attaching the tester lead to the ABS (ABS/TCS) HU/CM harness connector, the SST (49 G066 

001) must be used. (See 

P–29 ABS (ABS/TCS) HU/CM INSPECTION

.)

DTC

C1148, C1234
C1158, C1233
C1168, C1235
C1178, C1236

RF wheel-speed sensor/sensor rotor
LF wheel-speed sensor/sensor rotor
RR wheel-speed sensor/sensor rotor
LR wheel-speed sensor/sensor rotor

DETECTION 

CONDITION

• C1148, C1158, C1168, C1178: 

— Abnormal sensor output is detected on any of four vehicle wheels when the vehicle goes from start 

to a speed of 10 km/h {6.2 mph}.

— Greater than specified amount of ABS demand occurs from front wheel sensors when vehicle is 

started.

• C1234, C1233, C1235, C1236: 

— Abnormal sensor output due to chipping of sensor rotor teeth, etc. is detected
— ABS control operates for 60 seconds or more

POSSIBLE 

CAUSE

• Short to ground circuit of wheel-speed sensor(s) circuit

• Malfunction of ABC wheel-speed sensor(s)

• Damaged sensor rotor(s)

• Incorrect clearance between ABC wheel-speed sensor and sensor rotor

• Poor installation of ABC wheel speed sensor and/or sensor rotor (If the sensor rotor is installed twisted, 

it may cause output of abnormal wave form at high speeds.)

• ABS (ABS/TCS) HU/CM internal damage (Solenoid valve malfunction, pump motor malfunction, or pipe 

clogging)