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Home >> Nissan-Datsun >> 2000 >> Quest GLE >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics - 3.3 >> Diagnostic Tests >> DTC P0450: EVAP Control System Pressure Sensor (EVAP-CSPS) >> Test Procedure
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Test Procedure

  1. Check EVAP-CSPS hose for blockage or leak. See Fig 1. If problem exists, repair hose as necessary and retest system. If problem does not exist, loosen and retighten engine ground bolts. See Figure. Disconnect EVAP-CSPS harness connector. Check for water in connector. If water is present, repair or replace connector and retest system. If water is not present, go to next step.
  2. Turn ignition on. Measure voltage between ground and EVAP-CSPS harness connector Brown wire. If voltage is not about 5 volts, repair open or short in Brown wire. If voltage is about 5 volts, turn ignition off. Check continuity between ground and EVAP-CSPS harness connector Green wire. If continuity exists, go to next step. If continuity does not exist, repair open in Green wire.
  3. Check for short to power and short to ground in Green wire between ground and EVAP-CSPS harness connector. If problem exists, repair Green wire as necessary. If problem does not exist, go to next step.
  4. Disconnect ECM harness connector. See Figure. Check continuity of Red wire between EVAP control system pressure sensor harness connector and ECM harness connector terminal No. 62. See Figure. If continuity exists, go to next step. If continuity does not exist, repair open in Red wire.
  5. Check for short to power and short to ground in Red wire between EVAP control system pressure sensor harness connector and ECM harness connector terminal No. 62. If problem exists, repair Red wire as necessary. If problem does not exist, go to next step.
  6. Check EVAP-CPVCV. See DTC P0443: EVAP CANISTER PURGE VOLUME CONTROL VALVE (EVAP-CPVCV) . If problem exists, replace EVAP-CPVCV. If problem does not exist, check EVAP-CVCV. See DTC P0446: EVAP CANISTER VENT CONTROL VALVE (EVAP-CVCV) . If problem exists, replace EVAP-CVCV and retest system. If problem does not exist, go to next step.
    CAUTION: DO NOT apply more than 5.91 in. Hg of vacuum to EVAP-CSPS. DO NOT reuse EVAP-CSPS that has been dropped from a height of 20" (.5 m) or more onto a hard surface such as concrete.
  7. Remove EVAP-CSPS with harness connector connected. Disconnect hose from EVAP-CSPS. Turn ignition on. Using a hand vacuum pump, apply vacuum to EVAP-CSPS. With vacuum as specified, measure voltage between ground and ECM harness connector terminal No. 62 by backprobing. See Figure. See EVAP CONTROL SYSTEM PRESSURE SENSOR VOLTAGE  table. If voltage is not as specified, replace EVAP-CSPS. If voltage is as specified, go to next step.
  8. Check for blockage in water separator and EVAP-CVCV hose. If problem exists, clean or repair as necessary and retest system. If problem does not exist, check EVAP canister for water. See P0440 OR P1440: EVAP CONTROL SYSTEM SMALL LEAK . If problem exists, replace canister. If problem does not exist, go to next step.
  9. Reconnect all connectors. Disconnect Gray 8-pin connector M-119 located near EVAP canister. Check continuity between ground and connector M-119 terminal No. 5. See Fig 2. If continuity exists, go to next step. If continuity does not exist, repair open ground circuit.
  10. No problem is indicated at this time. Problem may be intermittent. See TESTING PROCEDURE under SELF-DIAGNOSTIC SYSTEM in SELF-DIAGNOSTICS - INTRODUCTION article.
EVAP CONTROL SYSTEM PRESSURE SENSOR VOLTAGE

Pressure Volts
Atmospheric Pressure 3.0-3.6
2.76 in. Hg .4-.6
Fig 1: Locating EVAP Control System Pressure Sensor (EVAP-CSPS)
G99E50462Courtesy of NISSAN MOTOR CO., U.S.A.
Fig 2: Identifying Connector M-119 Terminals
G99B51889Courtesy of NISSAN MOTOR CO., U.S.A.
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