Formulized94

iTrader: (68)

DBW conversion harness giving me a fit. I pulled all the transmission controls and cruise control out of the harness. The engine will idle no problem, fires up like a champ. However, it will not throttle at all. Push the gas pedal and nothing changes. The only code I am getting is p0122. I have changed pedals, matching tac modules, and tps. This engine has the corvette looking truck throttle body on it with the black plastic tab tac. When ign power is turned out, the throttle will "zero" or set, but nothing happens after that.

Anyone had this happen? I have done these harnesses, kept all the trans pigtails, and they worked awesome. I am hoping it is a simple fix and I know what to do next time.

Engine is a 2002 5.3

green96ta

iTrader: (11)

Please post a picture of the components and the numbers off of the pedal and tac. Unless you know for sure what year make and model the came out of then please post them.

Formulized94

iTrader: (68)

Everything is from a 2002 5.3.

Top right throttle body is what I am using.


This is the tac module I am using.

ls1nova71

iTrader: (4)

What PCM/tune are you using? Are your PCM connectors blue and red or blue and green? I had this same problem trying to use the wrong tune.

Redbull87

iTrader: (3)

sounds tune related to me,was the ecm from a cable tb car/truck and hasnt been flashed yet?

garys 68

iTrader: (1)

I've got the same setup off an 02 6.0.
Where did you get the TAC to pedal harness? Note VERY carefully the wiring. It's not simply A to A, B to B, etc.
If the ecu detects any issues with the pedal potentiometers, it will become non-responsive. I've had this happen a few times at startup after storage. A few pumps to clean the pedal takes care of it.

green96ta

iTrader: (11)

As stated, sounds like pcm is issue. You should be utilising a red/blue pcm. Preferrably a 12200411. Then you should be useing a vette or 6.0 calibration.

ls1_chevelle

iTrader: (9)

I bet its a dead Throttle Body.

Honda Hunter

iTrader: (8)

Did you get this figure out? Having same issue.

93BlackBeast

iTrader: (31)

I did the same swap in 2 vehicles...dbw setups with the pedals. I found out that some TAC modules from the junk yard I got them from were dead on arrival. Plug them up, start up engine or just key on, and have NO pedal/throttle body movement at all. Unplug the TAC module, plug a different one in...bam, worked. So, that's my best guess at the problem. Just try matching up different TAC modules to it and see if one fixes it. Good luck with your problems though.

Cody B.

conversion1972

I struggled with this and spoke with everyone that would listen. I received a lot of costly advise: new throttle body, new tac module, TPS, Harness, etc. It turned out that the power supply to the TAC that I had run was not switched. It must be a switched source.

Formulized94

iTrader: (68)

It ended up for me that the pcm had been swapped and I was not notified. Changed the flash in the pcm to a stock DBW setup... good to go.