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VREF Terminal Inspection




1. Turn The Ignition Switch To ON.




2. Measure the voltage between the throttle position
sensor connector (vehicle side) terminal A and body ground by using a voltmeter.
(1) When the measurement voltage is 0 V.
(1) Turn the ignition switch off.
(2) Disconnect the throttle position sensor
connector and fuel tank pressure sensor connector (which is applied Vref).




(3) Verify there is no continuity between the throttle position sensor connector (vehicle side) terminal A and body ground by using an ohmmeter.
(4) If there is continuity, repair the related harness.
(5) Inspect continuity between the PCM connector (vehicle side) terminal 31 and each sensor connector (vehicle side) terminals which is applied Vref by using an ohmmeter.
(6) If there is continuity, repair the related harnesses.
(2) When the measurement voltage is B +.
(1) Turn the ignition switch off.
(2) Disconnect the battery positive harness and battery negative harness.




(3) Verify there is no continuity between the throttle position sensor connector (vehicle side) terminal C and battery positive harness by using an ohmmeter.
(4) If there is continuity, repair the related harnesses.
(3) When the measurement voltage is approx. 5 V, Vref terminal (31) of PCM is okay.