ran power wire now i got error lights

I believe you can cycle the ignition on by pressing the button but not pushing the brake in.Kevin Pierson

Other vehicles I have worked with are one press / Accessory or press and hold, Ignition. Same as before, no foot on brake. Correction?: APP should read (5v, Signal, GND) x2 for both Potentiometers in the pedal assembly. (this is based on my experience, haven't run into a 12v pedal) Also to note, all of these wires should go back to the ECU directly. 5v and Gnd is supplied from ECU, and "Signal" is the return to the ECU. Chance of damage to the ECU is typically slim to none as they are intended to be short circuit protected. (Anything is possible though, especially if you were lucky enough to tag a 12v wire in the process) Make sure you have all the connectors seated well, some of them can be a bear to get them back in place. If you have the pinout, check for your 5v and GND at each POT with ignition on. Once you confirm you have voltage supply @ the pedal, you can measure voltage between signal and ground and see if it increases as you push the pedal. Don't expect the same voltage output from each POT, they are different for a reason. P2138 is the correlation fault between POTs. You could simply have a coincidentally bad pedal, or pierced a signal wire on POT1 or POT2 which is shifting the voltage seen by the ECU hence setting the correlation code. The service manual should give you a voltage spec at "Zero Pedal" for both POTs. Also, healing pedal faults can be difficult. Either multiple key cycles with passing fault detection or a scan tool to clear the codes. If the pedal tests out as expected but faults are not clearing you may need a scan tool to clear the codes.

Well I had it towed to my mechanic so we'll see what happens.. He said he's fixed stuff like this before so hopefully he can figure mine out.. I greatly appreciate all the replies.. I just didn't feel confident trying to fix..

Well.. Got it back tonight. My mechanic said I was missing a 5V reference to sensor 2 of accelerator.. He said he just spliced into another 5V wire.. All lights are good and seems to be functioning normal.. Price = $150

tbird2340 wrote: Well.. Got it back tonight. My mechanic said I was missing a 5V reference to sensor 2 of accelerator.. He said he just spliced into another 5V wire.. All lights are good and seems to be functioning normal.. Price = $150

so in other words he just put a band-aid on the symptom and ignored the actual problem... just a thought but did he even try to check for damaged wiring at the main harness where you were working? if not then the problem will most likely pop back up again and this time it will fry whatever other 5v source he tied into too.

Yea, that's what I'm wondering / afraid of too.. I doubt he tried to check for the damaged wire because it would have been in the grommet which is damn near impossible to get to without tearing the car apart (guessing).

But to what you were saying.. If the problem was a cut or nicked wire and the problem existed up until the point he fixed it.. Wouldn't it have fried that other circuit he tied into right then?

He said the wire tested open (cut) so I'm guessing I should be fine..

More then likely there is only one 5vdc output voltage from the ECU for all the 5vdc sensors so nothing was "fried". What the mechanic should have done is tested for power at the pedal, then tested for power at the ECU on the same wire. I would assume there would be power at the ECU but not pedal. The mechanic then should have cut the wire at the ECU, spliced a new wire to it, and ran it to the pedal. My assumption is that you broke the wire in the grommet. This most likely won't be an issue, but if it is in fact broken then it could work its way lose over time, short out and cause the ECU to shut down. To prevent this from ever happening the wire should be cut at the ECU and insulated. Also, do you know where he tapped the 5vdc feed from? If the mechanic used the other 5vdc feed that was going to the other potentiometer it would bypass part of the redundancy in the design of the DBW system. By design, if one 5vdc wire is broken or compromised the system should go in to limp mode and allow limited driving. However, if you use one 5vdc source to power both potentiometers and that wire gets compromised you will have no throttle ability at all. That is awesome that you were able to get it fixed relatively cheap though!Kevin Pierson

ECU should have at minimum 2 - 5v supplies (upwards of 4-5). The pedal alone is operating on 2 separate supplies as was mentioned. Without checking a wiring diagram, chances the the pedal has its own designated 5v is highly unlikely. It would be shared w some other sensor, whether it be a CAM sensor or the Throttle POT. So the idea of cutting the compromised 5V at the ECU and running a new wire isn't really possible, there are other sensors sharing that 5v feed. Isolating the broken wire would be best but may not be possible without tearing the car apart $$$$. 2nd best fix would have been running a new 5v feed from the correct ECU pin and cutting the factory wire and splicing the new wire at the Pedal. This would maintain the dual 5v feeds for redundancy/safety. I can not say as I blame you for you got lucky on an otherwise costly repair. I think the important thing is to understand how the repair was made and what potential impact if may have on future troubleshooting of the vehicle.