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Power Steering Pressure Switch System Test: Q45

  1. Start engine. Measure voltage between ground and ECM terminal No. 100 by backprobing. See Figure and Figure . Voltage should be about zero volts when steering wheel is being turned quickly. Battery voltage should exist when steering wheel is not being turned.
  2. If voltage is as specified, system is okay. If voltage is not as specified, turn ignition off. Disconnect Idle Air Control Valve-Fast Idle Control Device (IACV-FICD) harness connector. See Fig 1. Turn ignition on. Measure voltage between ground and IACV-FICD harness connector terminal No. 1 (Green/Yellow wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short circuit and retest system. See in appropriate wiring diagram in WIRING DIAGRAMS article.
  3. Turn ignition off. Reconnect IACV-FICD harness connector. Disconnect power steering pressure switch harness connector, located on high-pressure hose. Measure voltage between ground and power steering pressure switch harness connector terminal No. 1 (Green wire). If battery voltage exists, go to next step. If battery voltage does not exist, repair open or short circuit between IACV-FICD, ECM and power steering pressure switch. Retest system.
  4. Turn ignition off. Check continuity between ground and power steering pressure switch harness connector terminal No. 2 (Black wire). Also check circuit for short to voltage. Repair as necessary and retest system. If ground circuit is okay, go to next step.
  5. Disconnect ECM harness connector. Check continuity of Green wire between power steering pressure switch harness connector terminal No. 1 and ECM harness connector terminal No. 100. Also check circuit for short to ground and short to voltage. Repair as necessary and retest system. If circuit is okay, go to next step.
  6. Check power steering pressure switch. See POWER STEERING PRESSURE SWITCH . Check IACV-FICD. See RELAYS & SOLENOIDS . Replace components if necessary. If components are okay, go to next step.
  7. No problem is indicated at this time. Problem may be intermittent. See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
Fig 1: Locating IACV-FICD Harness Connector (Q45)
G99E51114Courtesy of NISSAN MOTOR CO., U.S.A.
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