Notes:
The Throttle Switch (TS) is invariable a three wire device operating at 5 volts (12 volts on very early systems). The objective of the throttle switch is to inform the Electronic Control Module (ECM) of the position of the throttle movement at throttle housing.
The example waveform shows a dual trace picture, monitoring the two switched terminals of the TS. The throttle has been operated from rest to full throttle and back to rest. The yellow trace is the idle contact circuit, once the throttle starts operating this switch opens and its voltage changes from 0 to 5 volts. It will remain at 5 volts, even at full throttle, until the throttle is back at its idle position.
The blue trace is the full load circuit and is at 5 volts (in its open position) until full throttle is achieved. As the operator
only stayed in the full throttle position for a very short period (560 ms) the switch soon opens again and the voltage changes back from 0 to 5.
This device can be switched in several ways, so it will be necessary to check with the vehicle and module specific data. Inside the switch there are two sets of contacts, this enables three stages of throttle movement to be monitored. These are: u Throttle closed u Throttle part open u Throttle fully open (sometimes referred to as wide open throttle - WOT )
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