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Throttle Position Sensor: Testing and Inspection

1. Remove ECM.
2. Connect couplers to ECM securely.
3. Warm up engine and stop it when its temperature has reached normal operating temperature.





4. Using voltmeter, check voltage at "B4" terminal under following conditions:

When clearance between throttle lever and throttle stop screw is less than 0.35 mm (0.014 in.): 0.2 - 1.0V
When throttle is fully open : 2.8 - 4.8V

If measured voltage is out of above specified range, diagnose trouble by referring to "Diagnostic Flow Chart for Diag. Trouble Code No.21 or 22". Also, check that voltage varies according to throttle valve opening linearly. If not, it is possible that TP sensor has failed. Replace.
5. Upon completion of checking, install ECM and connect ECM coupler securely.