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Home >> Toyota >> 2000 >> RAV4 Base, AWD, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 17 (Engine Control System Self-Diagnostics) >> Diagnostic Tests >> DTC P0450: EVAP Pressure Sensor Circuit, Or DTC P0451: EVAP Pressure Sensor Range/Performance >> Diagnosis & Repair
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Diagnosis & Repair

WARNING: This page is about a different car, the 2000 Toyota Corolla. However, it is still accessible from the selected car via links, so may be relevant.
  1. Access ECM below stereo, behind instrument panel, just in front of center console. Turn ignition on. Using DVOM, backprobe ECM harness connector. On models with 4A/T transmission, measure voltage between terminals No. 2 (Yellow wire) and No. 18 (Brown wire) at ECM harness connector E8. See Figure. On models without 4A/T transmission, measure voltage between terminals No. 1 (Yellow wire) and No. 9 (Brown wire) at ECM harness connector E5. See Figure. On all models, voltage should be 4.5-5.5 volts. If voltage is not as specified, replace ECM. If voltage is as specified, go to next step.
  2. Using DVOM, backprobe ECM harness connector. On models with 4A/T transmission, measure voltage between terminals No. 9 (Blue wire) and No. 18 (Brown wire) at ECM harness connector E8. On models without 4A/T transmission, measure voltage between terminal No. 17 (Blue wire) at ECM harness connector E4 and terminal No. 9 (Brown wire) at ECM harness connector E5. On all models, disconnect vacuum hose from vapor pressure sensor. See Figure. Connect a vacuum pump to vapor pressure sensor. Voltage should be 2.9-3.7 volts without vacuum applied and .5 volt or less with 1.8 in. Hg applied. If voltage is as specified, replace ECM. If voltage is not as specified, go to next step.
  3. Check for open or short in wiring between vapor pressure sensor and ECM. See WIRING DIAGRAMS article. If problem exists, repair wiring as necessary. If problem does not exist, replace vapor pressure sensor.
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