well another locked ecm.

[Scarface]

I got another locked ecm so this makes number 3 in the pile of locked ecms I have now. need to know if there is a place closer or in texas I can send these ecms to be unlocked. they all set the 0537 on them custom key

[GMC-2002-Dmax]

SoCal Diesel

Don't feel bad, I get them back all the time screwed up, especially the 2001's.

Just charge for the repair and send them out.

[Scarface]

I do charge for the repairs but damn. I even went and got a used ecm out of a running rolled over truck at the local junk yard and its locked as well. my luck on these lb7s.

[GMC-2002-Dmax]

This is why I have no less that 12 on hand at all times and at least a few out getting repaired at all times.

Makes it easy once you have a dozen or so.

[Scarface]

I been thinking of just seeing how many I can get out of the salvage yards that are good and get a bench harness to work on them

[comnrailpwr]

Forgive my ignorance as I don't tune many lb7. Probably only 20 to date. Are they being locked by tuners or are the ecm themselves corrupt? I have read something about the serial number getting corrupt. This what causes it?

[GMC-2002-Dmax]

The LB7 ECM can be corrupted quite easily, so a lot of times they are screwed but the vehicle will still run.

It's Ross's favorite ECM next to all the Bosch ones.

If you search here Ross has posted about it quite a bit, only option is to pull the flash chip and reprogram it off the board to fix it with an Eprom programmer.

[comnrailpwr]

Gotcha, thx.

[roughneck427]

I have two LB7 ECMs that I unlocked one took 3 days the other took 4. their serial numbers were all 000000000 and after flashing it with efi live they both say are not secured with any key and cant assign it a stock seed and key which is fine if someone doesn't want to lock them.

[Scarface]

I am trying to unlock one I got as a spare and one on a customer trucks. I got access at gm dealership to do a factory flash.

[GMPX]

Part of the problem is for quite some time GM's TIS2WEB was corrupting the LB7 when they updated them at the dealership. It would either (a) accidentally lock the ECM, (b) wipe clean the VIN and Serial Number, or both a and b. When they are locked GM's tool can't get around it either FWIW.
As Tony said when in that state the only option it is pulling the flash chip and programming it off board, easier said than done though, it's not like a Memcal from the 80's computers.
The 2001 specifically, this was the first release of that ECM, GM (or Isuzu) rewrote a lot of the code in the 2002+ models, they seem a lot more stable and less prone to corrupting themselves.

[Scarface]

so if I reflash it at the dealership would it be possible it might unlock it

[GMC-2002-Dmax]

Nope