DTC C1099


id060200800600

DTC

C1099

EPS motor

DETECTION CONDITION

• Abnormality detected in control current from EPS CM to EPS motor.

POSSIBLE CAUSE

• Open or short circuit in wiring harness between the following EPS CM terminals and EPS motor terminals:
- EPS CM terminal 3A-EPS motor terminal A
- EPS CM terminal 3B-EPS motor terminal B
• EPS CM malfunction
• EPS motor malfunction
• Poor connection of each connector

Diagnostic procedure

STEP

INSPECTION

ACTION

1
INSPECT WHETHER MALFUNCTION IS CAUSED BY POOR CONNECTION OF EPS CM OR PIN DEFORMATION
• Turn the ignition switch off.
• Inspect connection of the EPS CM and wiring harness.
• Disconnect the EPS CM connector.
• Inspect whether malfunction is caused by bent or poorly connected EPS CM connector pin.
• Are the connector connection, connector pins, and wiring harness normal?
Yes
Go to the next step.
No
Repair or replace the faulty connector wiring harness, then go to Step 5.
2
INSPECT EPS MOTOR CIRCUIT FOR OPEN CIRCUIT
• Disconnect the noise filter connector.
• Inspect for continuity between the EPS CM terminals and noise filter terminals.
- EPS CM terminal 3A-EPS motor terminal A
- EPS CM terminal 3B-EPS motor terminal B
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for open circuit between the EPS CM and EPS motor, then go to Step 5.
3
INSPECT EPS MOTOR CIRCUIT FOR SHORT TO POWER
• Measure the voltage between the EPS motor terminals and ground.
- EPS motor terminal A-ground
- EPS motor terminal B-ground
• Is there any B+?
Yes
Repair or replace the wiring harness for short to power between the EPS CM and EPS motor, then go to Step 5.
No
Go to the next step.
4
INSPECT EPS MOTOR CIRCUIT FOR SHORT TO GROUND
• Inspect for continuity between the EPS motor terminals and ground.
- EPS motor terminal A-ground
- EPS motor terminal B-ground
• Is there continuity?
Yes
Repair or replace the wiring harness for short to ground between the EPS CM and EPS motor, then go to the next step.
No
Replace the steering gear and linkage (EPS motor), then go to the next step.
5
VERIFY TROUBLESHOOTING COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the memory.
• Turn the ignition switch off.
• Start the engine.
• Is the same DTC present?
Yes
Replace the EPS CM, then go to the next step.
No
Go to the next step.
6
VERIFY AFTER REPAIR PROCEDURE
• Are any other DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC Table.)
No
DTC troubleshooting completed.