DESCRIPTION
The 4WD ECU assembly stores this DTC if a difference in tire size is detected.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area |
|---|---|---|---|
| C1337/91 | Diameter of the Tire is not Uniform | When the following continues for 36 seconds or more: At a vehicle speed of 30 km/h (18.6 mph) or more, the average speed difference between the front wheel and rear wheel is 4% or more. |
|
WIRING DIAGRAM
CAUTION / NOTICE / HINT
Note
When the 4WD ECU assembly is replaced with a known good one from another vehicle, it is necessary to perform calibration.
PROCEDURE
CHECK TIRE CONDITION
Check the size and condition of all 4 tires.
Tech Tips
This DTC is output when tire deformation or a difference in tire size is detected.
| OK |
|---|
| The diameter and air pressure of all 4 tires are the same. |
| Result | |||
|---|---|---|---|
|
| NG |
|
PERFORM AIR PRESSURE ADJUSTMENT OR REPLACE TIRES SO THAT ALL 4 TIRES ARE SAME IN SIZE Click here |
| OK |
|
CHECK FOR DTC
Clear the DTCs.
Start the engine.
Drive the vehicle at a speed of 30 km/h (19 mph) or more so that the same DTC is output.
Check if the speed sensor DTC (vehicle stability control system DTC) is output.
Read the DTCs using the GTS.
| Result | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
| B |
|
CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE - BRAKE ACTUATOR ASSEMBLY) Click here |
| C |
|
CHECK FOR INTERMITTENT PROBLEMS Click here |
| D |
|
REPAIR CIRCUIT INDICATED BY OUTPUT CODE (VEHICLE STABILITY CONTROL SYSTEM) Click here |
| A |
|
CHECK HARNESS AND CONNECTOR (SPEED SENSOR - BRAKE ACTUATOR ASSEMBLY)
Make sure that there is no looseness at the locking part and the connecting part of the connectors.
Turn the engine switch off.
Disconnect the A41 skid control ECU (brake actuator assembly) connector.
Disconnect the A92, A93, T1 and/or T2 speed sensor connector(s).
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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| Result | |||
|---|---|---|---|
|
Connect the A92, A93, T1 and/or T2 speed sensor connector(s).
Connect the A41 skid control ECU (brake actuator assembly) connector.
| OK |
|
GO TO STEP 6 Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE - BRAKE ACTUATOR ASSEMBLY)
Make sure that there is no looseness at the locking part and the connecting part of the connectors.
Disconnect the A41 skid control ECU (brake actuator assembly) connector.
Disconnect the A90, A91, T7 and/or T8 skid control sensor wire connector(s).
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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| Result | |||
|---|---|---|---|
|
Connect the A90, A91, T7 and/or T8 skid control sensor wire connector(s).
Connect the A41 skid control ECU (brake actuator assembly) connector.
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
INSPECT SKID CONTROL SENSOR WIRE
Make sure that there is no looseness at the locking part and the connecting part of the connectors.
Turn the engine switch off.
Disconnect the A90, A91, z20 and/or z21 front skid control sensor wire connector(s).
Measure the resistance according to the value(s) in the table below.
| *A | for RH | *B | for LH |
| *1 | Front Skid Control Sensor Wire | - | - |
| *a | Front view of wire harness connector (to Vehicle Side Connector) |
*b | Front view of wire harness connector (to Front Speed Sensor Side Connector) |
| Standard Resistance | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
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|
Connect the A90, A91, z20 and/or z21 front skid control sensor wire connector(s).
Disconnect the T7, T8, z22 and/or z23 rear No. 2 skid control sensor wire connector(s).
| *1 | Rear No. 2 Skid Control Sensor Wire RH |
| *2 | Rear No. 2 Skid Control Sensor Wire LH |
| *a | Front view of wire harness connector (to Vehicle Side Connector) |
| *b | Front view of wire harness connector (to Rear Speed Sensor Side Connector) |
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
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|
Connect the T7, T8, z22 and/or z23 rear No. 2 skid control sensor wire connector(s).
| Result | |||
|---|---|---|---|
|
| NG |
|
REPAIR OR REPLACE SKID CONTROL SENSOR WIRE |
| OK |
|
PERFORM TEST MODE (SIGNAL CHECK)
Turn the engine switch off.
Perform the sensor check in the Test Mode procedure.
| Tester Display |
|---|
| Signal Check |
| OK |
|---|
| All Test Mode (signal check) inspection items are normal. |
| Result | |||
|---|---|---|---|
|
| NG |
|
CHECK SPEED SENSOR ROTOR Click here |
| OK |
|
RECONFIRM DTC
Clear the DTCs.
Start the engine.
Drive the vehicle at a speed of 30 km/h (19 mph) or more and check that the same DTC is output.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| A |
|
CHECK FOR INTERMITTENT PROBLEMS Click here |
| B |
|
REPLACE BRAKE ACTUATOR ASSEMBLY Click here |
CHECK SPEED SENSOR ROTOR
Turn the engine switch off.
Remove the front speed sensor rotor (front axle hub sub-assembly) or rear speed sensor rotor (rear axle hub and bearing assembly).
for Front: Click here
for Rear: Click here
Check the speed sensor rotor.
| OK |
|---|
| There is no foreign matter, scratches or oil on the rotors. |
Tech Tips
If the front speed sensor rotor needs to be replaced, replace the front axle hub bearing assembly.
If the rear speed sensor rotor needs to be replaced, replace the rear axle hub and bearing assembly.
| Result | |||
|---|---|---|---|
|
| NG |
|
CLEAN OR REPLACE SPEED SENSOR ROTOR |
| OK |
|
REPLACE SPEED SENSOR
Turn the engine switch off.
Replace the front speed sensor or the rear speed sensor.
for Front: Click here
for Rear: Click here
| Result | ||
|---|---|---|
|
| NEXT |
|
RECONFIRM DTC
Clear the DTCs.
Start the engine.
Drive the vehicle at a speed of 30 km/h (19 mph) or more and check that the same DTC is output.
| Result | ||||||
|---|---|---|---|---|---|---|
|
Tech Tips
Reinstall the sensor, connectors, etc. and restore the vehicle to its prior condition before rechecking DTCs.
| B |
|
END |
| A |
|
REPLACE BRAKE ACTUATOR ASSEMBLY
Replace the skid control ECU (brake actuator assembly).
| Result | ||
|---|---|---|
|
| NEXT |
|
RECONFIRM DTC
Clear the DTCs.
Start the engine.
Drive the vehicle at a speed of 30 km/h (19 mph) or more and check that the same DTC is output.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| A |
|
END |
| B |
|
REPLACE 4WD ECU ASSEMBLY Click here |