NO.1 POOR POWER STEERING ASSIST

id060300800200

1
Poor power steering assist
Possible cause
•  EHPAS DTC is stored
•  Steering gear and linkage malfunction
•  Power steering fluid leakage from electro hydraulic power assist steering (EHPAS) fluid line
•  EHPAS control module malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION
1
CONFIRM EHPAS DTC
•  Perform the EHPAS DTC inspection using the M-MDS.
•   Is the symptom solved?
Yes
Record all DTC and go to the applicable DTC inspection.
(See ELECTRO HYDRAULIC POWER ASSIST STEERING (EHPAS) ON-BOARD DIAGNOSIS.)
No
Go to the next step.
2
VERIFY IF MALFUNCTION CAUSED BY LACK OF AIR BLEEDING FROM HYDRAULIC CIRCUIT
•  Bleed the air from the hydraulic circuit.
•  Is the power steering assist function changed?
Yes
Symptom troubleshooting completed. (Caused by lack of air bleeding from hydraulic circuit)
No
Go to the next step.
3
INSPECT STEERING WHEEL ASSIST FUNCTION
•  Disconnect the EHPAS control module connector (2-pin).
•  Is the power steering assist function changed?
Yes
Go to the next step.
No
Visually inspect the steering gear and linkage.
Replace the steering gear and linkage if the malfunction is found.
(See STEERING GEAR AND LINKAGE REMOVAL/INSTALLATION [L.H.D.].)
(See STEERING GEAR AND LINKAGE REMOVAL/INSTALLATION [R.H.D.].)
4
INSPECT IF THERE IS ANY FLUID LEAK FROM THE EHPAS FLUID LINE
•  Visually inspect the EHPAS fluid line.
•  Is there any fluid leakage?
Yes
Repair or replace the malfunctioning part according to the inspection result.
If there is oil leakage from the pump, replace the power steering oil pump.
(See ELECTRIC POWER STEERING OIL PUMP COMPONENT REMOVAL/INSTALLATION.)
(See ELECTRIC POWER STEERING OIL PUMP COMPONENT DISASSEMBLY/ASSEMBLY.)
No
Replace the EHPAS control module.
(See ELECTRIC POWER STEERING OIL PUMP COMPONENT REMOVAL/INSTALLATION.)