Hi, I have a 2004 Chevy Venture with the 3.4L. I have the P0122 code for the TPS low input signal. I check the 5V reference signal to the TPS and it is only reading ~ 0.14 V. I suspect there is a break in the gray reference wire somewhere between the TPS and the PCM. The reference signal from the PCM is feed from pin 33. Pin 33 only supplies the TPS. Pin 34, right beside Pin 33, also feeds a 5V reference signal to the Fuel Tank pressure sensor and the A/C pressure sensor. The 5V signal is good on this pin at the associated sensors. Since the A/C does not work, I was thinking it may be easier to just "steal" the 5V reference signal from the A/C sensor and use it for the TSP to avoid having to dig into the PCM wiring. Pin 33 is labeled "5V REF A" and Pin 34 is "5V REF B". Are you aware of any issues that would prevent this from not work? Thanks.

 

Could be the Throttle Position Sensor is bad.

 

The TPS did not have to be changed. It was OK, it was just not getting the 5v re fence signal from the PCM. Thanks for the suggestion though.

I ended up checking the reference signal right at pin 33 on the PCM and found there was 5v present. This confirmed I had a break in the reference signal wire between the PCM and the TPS.

Spliced in and a new wire directly to the TPS outside the wiring harness (I just abandoned the original wire in the harness - it was not obvious were the break was). TPS is now getting the 5v reference signal and the van is running like new again.