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Old 06-14-2021, 09:42 PM
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Default Reading Throttle Position Sensor Voltage

I have a GM throttle body that has a Throttle Position Sensor (TPS). In order to set the position of the throttle (at idle) you are supposed to read the voltage at 2 of the three pins. This sensor is basically a potentiometer. So, GM instruction are to pull the connector, turn the key on and read the voltage between the wiper (center) and the top pin.

I don't get it. If you remove the connector, you have removed the sensor entirely from any voltage any where. It's like measuring the sensor voltage if it was still in the box.

I gotta be missing something.
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Old 06-16-2021, 10:54 AM
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Quote:
Originally Posted by BBShark View Post
I have a GM throttle body that has a Throttle Position Sensor (TPS). In order to set the position of the throttle (at idle) you are supposed to read the voltage at 2 of the three pins. This sensor is basically a potentiometer. So, GM instruction are to pull the connector, turn the key on and read the voltage between the wiper (center) and the top pin.

I don't get it. If you remove the connector, you have removed the sensor entirely from any voltage any where. It's like measuring the sensor voltage if it was still in the box.

I gotta be missing something.
Use the ohm setting on the voltmeter (dc ohms). Pick a good range too. Not 2Mohn range for 120 ohms.

Then measure the source voltage. V=IR.

Or, poke a sharp probe into the wires and leave connected (at your own risk as this isn’t something I’ve seen pros do ).

Or buy connectors and make a dummy patch cable with extra leads on pins.

Last edited by rtj; 06-16-2021 at 10:56 AM..
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Old 06-16-2021, 01:29 PM
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I have a throttle body from a 1990 Corvette and have been looking at information about this adjustment from 20-30 year old sources. These old posts have been archived and pictures removed.

So, reading the text, I see that you removed the connector from the sensor. But your right, I didn't see that there was a jumper between the sensor and connector
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Old 06-16-2021, 04:14 PM
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Great. The technicians probably have an oem part.

Probably not too hard to rig up a one time use patch cable.
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