Component Description
| Component parts | Reference/Function |
|---|---|
| Power steering control unit | Signals from various sensors control the driving voltage to the power steering solenoid valve. The power steering control unit controls the driving voltage to the power steering solenoid valve for maintaining the power steering assist force when the fail-safe function is activated. (The engine speed signals control EPS system if any vehicle speed signal error is detected.) |
| Unified meter and A/C amp. | " DESCRIPTION " |
| ECM | " DESCRIPTION " |
| Power steering solenoid valve | " DESCRIPTION " |
Description
Power supply to EPS system
Power steering solenoid valve controls the power steering oil pressure in the gear housing assembly.
ECM sends engine speed signal to power steering control unit.
Scheme 16
- PERFORM ECM SELF-DIAGNOSIS With CONSULT Perform ECM self-diagnosis. Refer to " «DTC INDEX»(/infiniti/q60/i-2013-2016/remont/testing-diagnostics/#engine-control-system-diagnostic-codes-symptom-tests-usa-and-canada-coupe) " (For USA and Canada), " «DTC INDEX»(/infiniti/q60/i-2013-2016/remont/testing-diagnostics/#engine-control-system-diagnostic-codes-symptom-tests-mexico-coupe) " (For Mexico). Is any error system detected? YES: Check the error system. NO: GO TO 2.
- CHECK HARNESS BETWEEN ECM AND POWER STEERING CONTROL UNIT Turn the ignition switch OFF. Disconnect ECM harness connectors. Disconnect power steering control unit harness connector. Check the continuity between ECM harness connector and power steering control unit harness connector. ECM Power steering control unit Continuity Connector Terminal Connector Terminal M107 110 M108 10 Existed Also check harness for short to ground and short to power. Is the inspection result normal? YES: GO TO 3. NO: Repair or replace damaged parts.
- CHECK ENGINE SPEED SIGNAL (1) Turn the ignition switch OFF. Connect ECM harness connectors. Check the signal between ECM harness connector and ground with oscilloscope. ECM Value (Approx.) Connector Terminal Condition M107 110 - Ground Engine speed: At idle (Warm-up condition) Engine speed: Approx. 2, 000 RPM (Warm-up condition) Also check harness for short to ground and short to power. Is the inspection result normal? YES: GO TO 4. NO: Replace ECM. Refer to " «ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM): DESCRIPTION»(ref-660607-S11777260242014100600000) " (For USA and Canada), " «ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM): DESCRIPTION»(ref-660608-S31971507962014100600000) " (For Mexico).
- CHECK ENGINE SPEED SIGNAL (2) Turn the ignition switch OFF. Connect power steering control unit harness connector. Check the signal between power steering control unit harness connector and ground with oscilloscope. Power steering control unit Value (Approx.) Connector Terminal Condition M108 10 - Ground Engine speed: At idle (Warm-up condition) Engine speed: Approx. 2, 000 RPM (Warm-up condition) Also check harness for short to ground and short to power. Is the inspection result normal? YES: GO TO 5. NO: Replace power steering control unit. Refer to " «EXPLODED VIEW»(ref-660654-S27621179702014100600000) ".
- CHECK TERMINALS AND HARNESS CONNECTORS Check the power steering control unit pin terminals for damage or loose connection with harness connector. Check ECM pin terminals for damage or loose connection with harness connector. Is the inspection result normal? YES: INSPECTION END NO: Repair or replace damaged parts.
Unified meter and A/C amp. sends vehicle speed signal to power steering control unit.
Scheme 17
- PERFORM UNIFIED METER AND A/C AMP. SELF-DIAGNOSIS With CONSULT Perform unified meter and A/C amp. self-diagnosis. Is any error system detected? YES: Check the error system. NO: GO TO 2.
- CHECK HARNESS BETWEEN UNIFIED METER AND A/C AMP. AND POWER STEERING CONTROL UNIT Turn the ignition switch OFF. Disconnect unified meter and A/C amp. harness connector. Disconnect power steering control unit harness connector. Check the continuity between unified meter and A/C amp. harness connector and power steering control unit harness connector. Unified meter and A/C amp. Power steering control unit Continuity Connector Terminal Connector Terminal M66 8 M108 8 Existed Also check harness for short to ground and short to power. Is the inspection result normal? YES: GO TO 3. NO: Repair or replace damaged parts.
- CHECK VEHICLE SPEED SIGNAL (1) Turn the ignition switch OFF. Connect unified meter and A/C amp. harness connector. Check the unified meter and A/C amp. input/output standard values. Refer to " «REFERENCE VALUE»(ref-660633-S17271586312014100600000) ". Is the inspection result normal? YES: GO TO 4. NO: Replace unified meter and A/C amp. Refer to " «EXPLODED VIEW»(ref-660633-S19207269442014100600000) ".
- CHECK VEHICLE SPEED SIGNAL (2) Turn the ignition switch OFF. Connect power steering control unit harness connector. Check the signal between power steering control unit harness connector and ground with oscilloscope. Power steering control unit Value (Approx.) Connector Terminal Condition M108 8 - Ground Vehicle speed: 40 km/h (25 MPH) CAUTION: Check the air pressure of tire under standard condition. Also check harness for short to ground and short to power. Is the inspection result normal? YES: GO TO 5. NO: Replace power steering control unit. Refer to " «EXPLODED VIEW»(ref-660654-S27621179702014100600000) ".
- CHECK TERMINALS AND HARNESS CONNECTORS Check the power steering control unit pin terminals for damage or loose connection with harness connector. Check the unified meter and A/C amp. pin terminals for damage or loose connection with harness connector. Is the inspection result normal? YES: INSPECTION END NO: Repair or replace damaged parts.
Scheme 18
- Hard steering when fully turning the steering wheel.
- Light steering when driving at a high speed.