Ok guys,

I am having a helluva time with 3 of my work trucks. All three are having intermittent issues with the drive by wire system. I have replaced harnesses and traced wires, swapped good TAC modules, pedals, everything.

I have a 2003 2500 RCSB 2wd, 2004 2500HD CCSB, and a 2005 3500 CCLB.

All three trucks will randomly go into limp mode with throttle problems. P2135.

Is there an easy way to go to drive by cable? I have seen some descriptions, but does anyone have a picture step by step procedure?

Any help would be appreciated!

 

I would not suggest trying to swap to DBC because of the complexity of the swap and you said they are work trucks and not project vehicles. Have you tried the TPS sensor or MAF? Limp mode is triggered when the computer senses airflow is changing too quickly and it thinks something is wrong.

 

can't it also go into limp mode if the computer doesn't see the same voltage from the pedal to the throttle body returning back to the pedal? like a shorted wire that has more resistance in it?

 

That's the problem I am having, voltage correlation problems. I have ohmed out all of the wires going to the TAC module according to instructions in alldatadiy.com and cannot find one with higher resistance, or one with a short to ground. I have swapped TAC modules from trucks that do not have the problem and are assumed good, as well as swapping pedals.

The problem seems to be that since this is throttle related, the voltage miscommunication can be .001 of a second to initiate the code and limp mode.

Right now I have my guys rolling around with cheapo harbor freight code scanners to clear the code when it pops up. Happens once or twice a day.

 

Your issue is likely a bad pin in the throttle connector. I'd pull them all apart and check to see if one has oxidation/corrosion. It will ohm perfectly fine, the issue is when it hits a bump or gets hot it will encounter higher resistance.