Steering Wheel Turning Force Is Heavy or Light

TROUBLE DIAGNOSIS FOR SYMPTOMS


Steering Wheel Turning Force Is Heavy or Light


SYMPTOM:
Steering wheel turning force is heavy or light, while driving.

DIAGNOSTIC PROCEDURE
1.CHECK SYSTEM FOR CAN COMMUNICATION LINE
Perform self-diagnosis. Refer to CONSULT-III Function (EPS).
Is the "CAN COMM CIRCUIT [U1000]" displayed?
YES >> Perform trouble diagnosis for CAN communication line. Refer to C1606 C1608 Steering Control System.
NO-1 >> With ABS: GO TO 2.
NO-2 >> Without ABS: GO TO 3.
2.CHECK VEHICLE SPEED SIGNAL FROM ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
Perform self-diagnosis with ABS actuator and electric unit (control unit). Refer to Scan Tool Testing and Procedures.
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 4.
3.CHECK VEHICLE SPEED SIGNAL FROM TRANSMISSION CONTROL MODULE (TCM)
Perform self-diagnosis with TCM. Refer to CONSULT-III Function (Transmission).
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 4.
4.CHECK COMBINATION METER SIGNAL
Perform self-diagnosis with combination meter. Refer to Scan Tool Testing and Procedures.
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 5.
5.CHECK ENGINE STATUS SIGNAL
Perform self-diagnosis for ECM. Refer to For California.
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 6.
6.CHECK EPS MOTOR SYSTEM
Perform trouble diagnosis for EPS motor. Refer to C1606.
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
7.CHECK EPS CONTROL UNIT
Check EPS control unit input/output signal. Refer to EPS Control Unit Input/Output Signal Reference Value.
OK or NG
OK >> GO TO 8.
NG >> Check EPS control unit pin terminals for damage or loose connection with harness connector. If any items are damaged, repair or replace damaged parts.
8.SYMPTOM CHECK
Check again.
OK or NG
OK >> INSPECTION END
NG >> Check the steering wheel turning force because there may be mechanical malfunction. Refer to Component Tests and General Diagnostics.