Help: LB7 ECM trouble

[ikeG]

Got a 02 LB7 here, heres the story. Trans is slippin when converter is locked, keeps goin into limp mode. Runs really well, no dsp switch. Tried to pull ECM file, says locked. Decided to have GM reflash to stock with Tech II. They say the had trouble. Brought it back, same issues.
NOW, the thing will only crank for a while, run just for a split second, then shut off. Security light on all the time. Setting these codes: U1041, U1096, U1064, and U1000. What might be the issues? I unplugged the bale connectors, looked at those pins. seemfine.

 

[whytry]

Call guy tripp

 

[ikeG]

Went and pulled a bunch of fuses, none were blown. Security light back to normal, fires up and runs fine now. ????

 

[ikeG]

The vin is a bunch of jibberish in the scan tool , too.

 

[MACKIN]

What's any of that have to do with the transmission slipping? Sounds like possibly there was a different then stock calibration in the ECM and that's why perhaps there was a issue at the dealer. Then it was flashed with a 02 stock calibration then the vats kicked in. How it reset who knows but it's working fine so no worries.

Now investigate the slipping transmission.

 

[ikeG]

Want to put stock tune in to see if trans still slips. People are not wanting to build it. They bought it with this tuning in it. Trying to reflash @ dealer opened another can of worms. Does it sound like the ECM is toast? vin stored is heiroglyphics.

 

[MACKIN]

If it slips it slips so it's going to need repair . Truck runs with the dealer flash so you've said so what is the issue? What are u using to read the ECM? Looks like you have EFI

 

[ikeG]

It only ran for 5 mile to get home, then after shut off, only crank for a while, run just for a split second, then shut off. Security light on all the time. Setting these codes: U1041, U1096, U1064, and U1000. Pulled fuses, problem now gone. VIN in ecm is in jibberish. Is the ECM toast or what?

 

[MACKIN]

Not understanding the DTC codes. I truly cannot tell you if your ECM is toast. You say problem is solved so it runs ok? I'd assume if it was toast the truck wouldn't run. If it repeats then find a used ECM and with your EFI You should be able to flash a stock 02 calibration in it. I'm sure someone has it here and would be willing to give it to you.

Good luck

 

[lb7blksmk]

You can try checking the heath status but every time ive seen jiberish as the vin its been lost.

 

[DAVe3283]

My roadrunner ECU reads gibberish as the VIN but runs fine.

Try checking the health, and if it's OK, try a full flash. I would assume a gibberish VIN is not a good sign on a non-roadrunner ECU. You might be in the market for a replacement ECU soon, sorry.

Sent from my Galaxy Nexus using Tapatalk 2

 

[adeso]

I would try a full flash of both the ECM and TCM with a good tune. But I'm not really smart when it comes to working with the actual ECM so I’m just guessing here

 

[rgullett83]

i am guessing the ecm needs replaced due to the reflash issues, the DTCs that start with U are communication dtcs ie, between different modules on the data bus. My 01 had a corrupt ECM when i bought it, had no running issues, I just couldnt read it or flash it when the time came. I bought a used ECM from Guy at socal, flashed in an 02 OS, and have not had any troubles since.

 

[whytry]

Guy at socal can help you....he will fix your ecm for cheaper then a new one.. He knows ecms...just sayin been there before with corrupt ecms

 

[ikeG]

I cannot pull the file thats in it; it is locked with a custom key. That means i cannot full flash over it, can I?