U0107, red/blue pcm, and dbw question
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U0107, red/blue pcm, and dbw question Finally finished my swap, truck fires up and idles fine. Will run fine indefinitely with some throttle. Once I step on it, I can continue to flog it if I don't let it go back to idle, but if I do I lose all throttle response. Pretty standard with U0107.
I know U0107 can be caused by a couple things, usually grounding issues, or a mismatched TAC and/or pedal.
My engines a 2006, pedal and TAC are 2006, but my PCM has red and blue connectors. Everywhere I've seen says red/blue connectors are from 99-02, but all my components came out of the same donor. Could this be causing my problems?
EDIT: I checked and do not have red/blue pcm, it's green/blue as it should be
As far as grounding issues go, if I read 12.6 everywhere am I good? I read 12.6 on the pink wire off the tac, and the black wire is grounded.
Really blows right when you think you've finished your swap you got a problem you can't even diagnose, so any help is greatly appreciated.
I know U0107 can be caused by a couple things, usually grounding issues, or a mismatched TAC and/or pedal.
My engines a 2006, pedal and TAC are 2006, but my PCM has red and blue connectors. Everywhere I've seen says red/blue connectors are from 99-02, but all my components came out of the same donor. Could this be causing my problems?
EDIT: I checked and do not have red/blue pcm, it's green/blue as it should be
As far as grounding issues go, if I read 12.6 everywhere am I good? I read 12.6 on the pink wire off the tac, and the black wire is grounded.
Really blows right when you think you've finished your swap you got a problem you can't even diagnose, so any help is greatly appreciated.
Last edited by A.Ezz; Jun 13, 2015 at 08:46 PM.
does your pcm say red and blue in it? if it does, wrong pcm. get a blue/green pcm. im not even sure how you managed to hook up a red/blue pcm as you have to cut a small fin on the connectors if you have a green and blue harness.
"My engines a 2006, pedal and TAC are 2006, but my PCM has red and blue connectors."
so does your harness have a blue and red connector ends? or does the pcm say blue and red on it? i am confused on what you have. if your harness has blue and red connectors you dont have the proper harness, if your computer has red and blue marked somewhere in there you have the improper pcm considering its not a p59 from a vette, ctsv, or gto or express van...
idk if i can be any more clearer than that.
so does your harness have a blue and red connector ends? or does the pcm say blue and red on it? i am confused on what you have. if your harness has blue and red connectors you dont have the proper harness, if your computer has red and blue marked somewhere in there you have the improper pcm considering its not a p59 from a vette, ctsv, or gto or express van...
idk if i can be any more clearer than that.
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Verdad Gallardo where did you get that harness from? certainly not a silverado/suburban, must have been a gto, vette, cts v, or express van correct? never seen an 06 red and blue harness in a silverado/suburban variants and i have tuned A LOT of silverados.
i have never ever seen red/blue connectors on an 06 harness from a silverado. i have tuned at least 500 silverados and all of them always, 99-02 red and blue, 03+green and blue . i seriously recommend you look into getting a proper blue/green silverado harness to fix your issues as well as a blue/green pcm.
Subeone is correct there was no red / blue PCM's used in gas trucks after 2002, even the S10 chassis switched to the blue / green PCM's in 2003. Since you most likely already modified your harness for your swap you might be better off swapping out the tac and posiably the pedal. Which thrortle body do you have the single connector one or the one with the seperate tps plus?
2006 PCM should say blue and green on it. 2001-2002 DBW trucks used a different TAC module and TB than 2003-2005. 2003-2005 TAC module has a metal back, the earlier one is all plastic. Earlier TB has 2 conectors, a 6 pin and 2 pin. Newer TB has a single 8 pin. Pedal and TAC module changed again is 2006.
U0107 will also set if the PCM and TAC module are not both powered up together. i.e. if one powers up first or remains powered after the other shuts down.
U0107 will also set if the PCM and TAC module are not both powered up together. i.e. if one powers up first or remains powered after the other shuts down.
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Well I feel like an idiot right now. Been a while since I've seen my pcm with the harness off, double checked this morning and it is a blue green one.
So now it seems all my components match up, but I'm still getting U0107
So now it seems all my components match up, but I'm still getting U0107
If both harness and PCM are green/blue, and you also have a 2006 TAC module and pedal.....
Check for 12V to the TAC module or 5V at the TB connector with the key on(GRY and BLU/BLK wires)... and that the throttle blade "clicks" at key-on. Should be no power to the TAC module with key off. Make sure that ignition and relays are wired so that both PCM and TAC module power up/down together.
Check for 12V to the TAC module or 5V at the TB connector with the key on(GRY and BLU/BLK wires)... and that the throttle blade "clicks" at key-on. Should be no power to the TAC module with key off. Make sure that ignition and relays are wired so that both PCM and TAC module power up/down together.
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I have 12V at the tac and the ground is good as well. I'm not sure if my multimeter is off but I read 4.98 at two terminals, 4.1 at two terminals, and 0 at the rest. Is that as it should be?
The "clicks" you're talking about, is that literally an audible click that I should hear at key on?
Also, I thought the TAC (or maybe throttle position sensor?) is always on? Or is that how it's wired from the factory and I have to change that?
The "clicks" you're talking about, is that literally an audible click that I should hear at key on?
Also, I thought the TAC (or maybe throttle position sensor?) is always on? Or is that how it's wired from the factory and I have to change that?
I have 12V at the tac and the ground is good as well. I'm not sure if my multimeter is off but I read 4.98 at two terminals, 4.1 at two terminals, and 0 at the rest. Is that as it should be?
The "clicks" you're talking about, is that literally an audible click that I should hear at key on?
Also, I thought the TAC (or maybe throttle position sensor?) is always on? Or is that how it's wired from the factory and I have to change that?
The "clicks" you're talking about, is that literally an audible click that I should hear at key on?
Also, I thought the TAC (or maybe throttle position sensor?) is always on? Or is that how it's wired from the factory and I have to change that?
Probably normal readings. The throttle blade quickly closes then returns to the cranking position as part of the self tests when you turn the key-on...unless something else has already triggered REP before the self-tests run. You can definitely hear the blade snap closed and back.
Should be no power to the TAC module with key off. Otherwise it will try to communicate with the PCM, which has its processor powered down. The TAC module will store a U0107(loss of communication between TAC and PCM) that will already be there as soon as you turn the key on, thereby triggering REP.
I grabbed this pic from the 2004 manual, but wiring should be similar.
Last edited by DrX; Jun 6, 2015 at 07:57 PM.