Nissan Altima 2007-2012 Service Manual: ECU diagnosis

POWER STEERING CONTROL UNIT

Reference Value

TERMINAL LAYOUT

PHYSICAL VALUES

CAUTION: When using circuit tester or oscilloscope to measure voltage for inspection, be sure not to extend forcibly any connector terminals.

Wiring Diagram — ELECTRONICALLY CONTROLLED POWER STEERING SYSTEM

Fail Safe

EPS system

• EPS system enters the fail-safe mode (that allows the steering force to be controlled without impairing the drive ability) if any of the input/output signals to/from EPS system (power steering control unit) deviate from the standard.

NOTE: The system enters the fail-safe mode if the engine speed remains at 1,500 rpm or more for over 10 seconds while the vehicle is stopped. This is normal.

• The fail-safe function is canceled when a vehicle speed signal of 2 km/h (1.2 MPH) or more is inputted or the key switch is turned OFF→ ON. EPS system restores the normal operation at that time.

    Vehicle speed signal circuit
    Description • Combination meter sends vehicle speed signal to power steering control unit. Diagnosis Procedure 1.PERFORM COMBINATION METER SELF-DIAGNOSIS Perform combination meter self-diagno ...

    Symptom diagnosis
    UNBALANCE STEERING WHEEL TURNING FORCE (TORQUE VARIATION) Description • Hard steering when fully turning the steering wheel. • Light steering when driving at a high speed. Diagnosis Proce ...

    Other materials:

    Diagnosis and repair workflow
    Work Flow OVERALL SEQUENCE • Reference 1··· Refer to AV-289, "CONSULT - III Function (MULTI AV)". • Reference 2··· Refer to AV-424, "Symptom Table". DETAILED FLOW 1.CHECK SYMPTOM Check the malfunction symptoms by performing the following items. • Intervie ...

    BCM branch line circuit
    Diagnosis Procedure INSPECTION PROCEDURE 1.CHECK CONNECTOR 1. Turn the ignition switch OFF. 2. Disconnect the battery cable from the negative terminal. 3. Check the terminals and connectors of the BCM for damage, bend and loose connection (unit side and connector side). Is the inspect ...

    B1081 – B1084 seat belt pre-tensioner RH
    Description DTC B1081 – B1084 SEAT BELT PRE-TENSIONER RH The seat belt pre-tensioner RH is wired to the air bag diagnosis sensor unit. The air bag diagnosis sensor unit will monitor for opens and shorts in detected lines to the seat belt pre-tensioner RH. PART LOCATION Refer to SRC-7, &qu ...