NO.3 POWER ASSIST DIFFERS BETWEEN RIGHT AND LEFT TURNS

id060300801000

3
Power assist differs between right and left turns.
TROUBLESHOOTING HINTS
•  Steering gear and linkage malfunction
―  Steering gear sticking
―  Tie-rod end sticking
•  EPS motor malfunction
•  Torque sensor malfunction
•  Resolver sensor malfunction
•  EPS control module malfunction
•  EPS control module connector connection, terminal malfunction
•  EPS system neutral position setting not performed (DTC C200B:54 is output)
•  Wheel alignment misadjusted
•  Front tire condition (air pressure, wear-out condition) different between left and right

Diagnostic procedure

Step

Inspection

Action
1
DETERMINE IF MALFUNCTION CAUSE IS FRONT WHEEL ALIGNMENT OR EPS SYSTEM (STEERING GEAR AND LINKAGE INCLUDED)
•  Does the malfunction phenomenon occur only while the vehicle is driven?
Note
•  Verify on level road.
Yes
Inspect the following and repair the malfunctioning location.
•  Tire air pressure
•  Front wheel alignment
(See FRONT WHEEL ALIGNMENT [European (L.H.D., U.K.) Specs.].)
(See FRONT WHEEL ALIGNMENT [Australian Specs. and General (L.H.D., R.H.D.) Specs.].)
No
Go to the next step.
2
INSPECT EPS CONTROL MODULE FOR DTCs
•  Perform the DTC inspection for the EPS control module using the M-MDS.
•  Are any DTCs output?
Yes
Go to the applicable DTC inspection.
(See ELECTRIC POWER STEERING (EPS) ON-BOARD DIAGNOSIS.)
No
Go to the next step.
3
INSPECT FOR MALFUNCTIONS IN TORQUE SENSOR SYSTEM OR OTHER CAUSES
•  Jack up the vehicle.
•  Start the engine.
•  Can the following conditions be verified?
―  Steering wheel turns instantaneously right after engine is started
―  Steering wheel turns on its own.
―  The PID data monitor is not around 0 N·m when steering wheel is not steered.
•  SS_TRQ1
•  SS_TRQ2
Yes
Inspect the wiring harnesses of the torque sensor and repair or replace if there is a malfunction.
If there is no malfunction in the wiring harness, replace the steering gear and linkage. (torque sensor malfunction)
(See STEERING GEAR AND LINKAGE REMOVAL/INSTALLATION [L.H.D.].)
(See STEERING GEAR AND LINKAGE REMOVAL/INSTALLATION [R.H.D.].)
No
Go to the next step.
4
DETERMINE IF MALFUNCTION IS IN STEERING GEAR AND LINKAGE
•  Disconnect the EPS motor connector.
•  Release the steering lock.
•  Compare the steering wheel force to the left and right.
•  Is the steering wheel force the same to the left and right?
Yes
Go to Step 6.
No
Go to the next step.
5
INSPECT TIE-ROD END ROTATION TORQUE
•  Measure the rotation torque of the tie-rod end.
•  Is the tie-rod end rotation torque normal?
Yes
Replace the steering gear and linkage.
(See STEERING GEAR AND LINKAGE REMOVAL/INSTALLATION [L.H.D.].)
(See STEERING GEAR AND LINKAGE REMOVAL/INSTALLATION [R.H.D.].)
No
Replace the tie-rod end.
(See STEERING GEAR AND LINKAGE DISASSEMBLY/ASSEMBLY.)
6
DETERMINE IF MALFUNCTION IS IN EPS MOTOR OR RESOLVER SENSOR
•  Connect the EPS motor connector.
•  Start the engine with the vehicle jacked-up and idle the engine.
•  Compare the steering wheel force to the left and right.
•  Is the steering wheel force to the left and right the same?
Yes
Replace the EPS control module.
(See EPS CONTROL MODULE REMOVAL/INSTALLATION.)
No
Inspect the wiring harnesses of the EPS motor and resolver sensor and repair or replace if there is a malfunction.
If there is no malfunction in the wiring harnesses, replace the steering gear and linkage. (EPS motor or resolver sensor malfunction)
(See STEERING GEAR AND LINKAGE REMOVAL/INSTALLATION [L.H.D.].)
(See STEERING GEAR AND LINKAGE REMOVAL/INSTALLATION [R.H.D.].)