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Code p2128

I have a code p2128 comes on every couple of days after i claer It .

how to repair?

2006 Ion saturn 66000 miles

DTC P2128=Accelerator Pedal Position Sensor 2 Circuit High Voltage.

The problem could be with the sensor or the sensor circuit.


You’re gonna need a scanner for this one.

I have a scanner I was looking to see if anybody has had thius problem
Thank you

There is no “how to repair” - all you have is a code, not a diagnosis.

The circuit & sensor have basic specs. Find out what they are and test.

Autozone’s online repair info is free and might give you the specs. There’s likely at the very least a 5V ref signal that the sensor is supposed to get. Then the sensor itself is likely some kind of variable resistance type of device, that’s probably supposed to have a resting voltage that changes when the pedal moves. Then whatever it produces for voltage has to make it back out to the PCM. Those are assumptions based on how a lot of things work - find the specs and test.

When you say a scanner do you mean a code reader? B/c pete p was likely talking about a scantool that provides full real time data on the systems. If all you have is a code reader you can probably get by on the testing with a DVOM.

Before throwing parts at it, I would do a Google search of this issue now and see what the most common fix for this is, whether you replace the sensor, the harness or something else. When I did that search putting “2006 Ion Saturn Accelerator Pedal Position Sensor 2 Circuit High Voltage” in the search criteria, I found the most common resolution to this specific issue, was replacing the TP sensor which is attached to (or a part of) the Throttle Body… Sometimes we don’t have the fancy tools and meters to read the volts and ohms and all that and so it is easier (and hundreds of $$$$ cheaper) to find out what others have discovered. So far this method has never let me down. That is how I determined an issue with my truck (see my OBD II thread) and the issue is gone.

A digital or analog volt-ohm meter is not a fancy or expensive tool. Yet it is a very useful one that every person trying to do auto electrical diagnostic work should have. Well, that and a test light. Meter at radio shack:
test light about the same or less, or make one out of a 12v bulb and 2 pieces of wire. So to you its cheaper to just replace parts than to see what parts need to be replaced. I guess that’s OK if you are part of the “more dollars than sense” crowd. But then again I just like solving the problem over the “oh well this part didn’t do it what can I replace next.” That your “let’s try what every one else did” works for you is great. But it may not always work for you or anyone else all the time. And the time it does fail you will probably wish you had all these cheap simple diagnostic aids.