Direct Type

With this type of throttle sensor, signals are input directly to the ECT ECU from the throttle position sensor. Three movable contact points rotate with the throttle valve, causing contacts L1, L2, L3 and IDL to make and break the circuit with contact E (ground). The grid which the contact points slide across is laid out in such a way as to provide signals to the ECT ECU depicted in the chart below. The voltage signals provided to the ECT ECU indicate throttle position just as they did in the indirect type of sensor.

If the idle contact or its circuit on either throttle sensor malfunctions, certain symptoms occur. If it is shorted to ground, lock-up of the torque converter will not occur. If the circuit is open, neutral to drive squat control does not occur and a harsh engagement may be the result. If the L1, L2, L3 signals are abnormal, shift timing will be incorrect.

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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