Nissan Altima (L32) 2007-2012 Service Manual: Function diagnosis
EPS SYSTEM
System Diagram
CONTROL DIAGRAM
System Description
• The EPS system controls the power steering solenoid valve through the power steering control unit.
• The valve driving voltage to control the power steering solenoid valve varies according to the vehicle speed.
OPERATION PRINCIPLE
During Parking (When Turning The Steering Wheel To The Right)
1. Power steering solenoid valve is closed while a vehicle is stopped.
2. Pinion "1R", "2R" and "3R" are closed depending on steering torque of steering wheel.
3. Oil pressure "P" in the gear housing assembly is the sum of oil pressures occurred in "2R" and "3R". This results in a light steering force because of high pressure.
During High-speed Operation
1. Power steering solenoid valve is opened during high-speed operation.
2. Pinion "1R", "2R" and "3R" are closed depending on steering torque of steering wheel.
3. Oil pressure "2R" does not occur because the power steering solenoid valve is on full throttle.
4. Oil pressure "P" in the gear housing assembly includes only oil pressure occurred in "3R" and results in a heavy steering force.
Component Parts Location
1. Power steering control unit M59 (view with glove box removed)
2. Power steering solenoid valve E14
Component Description
Basic inspection
DIAGNOSIS AND REPAIR WORKFLOW
Work Flow
DETAILED FLOW
1.COLLECT THE INFORMATION FROM THE CUSTOMER
It is also important to clarify customer complaints before inspection. First
of all, reproduce s ...
Other materials:
BCM
Diagnosis Procedure
1. CHECK FUSE AND FUSIBLE LINK
Check if the following BCM fuse or fusible link are blown.
Is the fuse or fusible link blown?
YES >> Replace the blown fuse or fusible link after repairing the affected
circuit.
NO >> GO TO 2
2. CHECK POWER SUPPLY CIRCUIT
1. ...
Front power seat adjustment (if so equipped for driver’s seat)
Operating tips
WARNING
Before driving the vehicle, return the seatback
to an upright seating position after
manually releasing it. Also, make sure the
seat is locked in place. Failure to do so
may cause the seat to move in a collision
or sudden stop. This may result in damage
to the seat o ...
S connector circuit
Description
The starter motor magnetic switch is supplied with power when the ignition
switch is turned to the START position
while the selector lever is in the P or N position (CVT models) or the clutch
pedal is fully depressed (M/T
models).
Diagnosis Procedure
CAUTION:
Perform diagnosis ...
