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Fuel Pressure Regulator VSV Control Circuit

  1. Check fuel pressure regulator VSV. See FUEL PRESSURE REGULATOR VACUUM SWITCHING VALVE (VSV) . If VSV is okay, pull back the right front floor mat. Remove ECM protective cover. Connect Check Harness (09990-01000) between ECM and harness. See USING CHECK HARNESS  under INTRODUCTION. Turn ignition on.
  2. Measure voltage between chassis ground and terminal No. 73 (Blue/Red wire) of ECM connector "B". To identify ECM connectors and terminals, see Figure. If battery voltage is measured, VSV circuit is okay. If battery voltage is not measured, check circuit between ECM and VSV, and between VSV and EFI main relay. If circuit is okay, replace ECM.