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Testing TPS Values on Fuel Injection


BOT Machine
(throttle position switch)

Using a DVOM (digital volt ohm meter) ,the TPS signal wire should be the one furthest to the right on the sensor, it is grey purple and easy to find out one of the others is going to be ECM/chassis ground and the other 5V feed. You measure between the signal wire and chassis ground, preferably at the battery negative.Voltage specs are as follows. .41 for 01-03 and .52 for 04's in the idle position.
The values should increase smoothly as the throttle is opened to max voltage of 5V. The Problem is, is that you must also reset the IAC (intake air control) motor now that you have adjusted it. The later models are not adjustable. It can only be reset with a Scanalyzer or Digital Tech by the dealer through the ECM settings.

The older morelli bikes were adjustable with elongated slots in the TPS switch, but the delphi units are not adjustable and need to be replaced if they do not work correctly.

If you venture to remove the plug that covers the Idle setting screw to change this setting, the ECM will return the speed to where it was before you changed it and eventually set a code. Don't be tempted to do it, or it will throw other settings out also.