piece-of-cake?

[Glide]

Would it be worth trying new keys? I don't know if that will work. I always thought it would relearn any key?

No.If won't learn any of the keys you have I doubt that a new key would make any difference.
Having said that,I once had an issue learning keys to a Hyundai after BCM replacement.The owner didn't mention that one of his keys hadn't worked in a while,and as luck would have it the faulty key was the one that I tried to learn first which kicked me out of key teaching.Eventually I tried the other key first which learned,then the faulty key showed up as bad.So maybe you should try to learn the keys in a different order.

[Stalls]

I unfortunately have tried both keys in different orders..

[Witsend]

Sorry to revive this old thread
I am having almost the same exact problems with a 14 suburban that original poster Matt had. Even pretty dang close to the same info on screen shots.. I got the vehicle with no communication at all and obviously a result to no crank lol. Ended up diagnosing and replacing both the (new) bcm and (new) transfer case control module to get high speed communication working. Low speed needed (Used) instrument panel cluster and (new) theft deterrent module. All these modules had no communication what so ever and resulted in killing both high and low speed data. All data and modules communicate properly now.

New to aftermarket programming scene. Was a GM tech before at dealer. Programmed all modules successfully... Except the used cluster (that was working fine till I tried to update it) and now is dead I tried to program the IPC module last after my TDM wouldn't learn the keys. So out of bordem and while thinking on that I screwed up the cluster lol...

Vehicle won't crank or learn (to my knowledge) original keys although one is aftermarket... Another tid bit is the customer purchased this vehicle from auction in this condition and is in perfect shape with only 100k on it. No damage.. Any word of advice would be greatly appreciated! Thanks!

What would happen at this stage if you disconnected the battery and reinstalled the original Body Control Module and Instrument Cluster back into vehicle(providing they don't smell burn't or appear damaged)?

[Stalls]

The old bcm makes things go crazy. Wipers and lights go on along with other things. The old instrument cluster I haven't tried but it did not communicate at all. But the lights and system message center does work on the old one.

I thought about trying to reprogram the ecu that is currently in the vehicle and if that dont work try to get another used one and try that.. Any thoughts?

BTW! I did take the old theft deterrent that had a communication chip that was burnt. I soldered in a new one and it works and reads 3 keys are programmed.

[Witsend]

Don't ever under estimate the crazy electrical issues of what an old fashioned simple problem like a bad or loose power or ground connection can cause on a Hi tech POS.

[Stalls]

If I have full communication with the ecu and the vin is correct..

Here is a system run down

[Stalls]

Thats after a clear all..

[Witsend]

I think maybe I would rule out an interruption of 12v power supply (drop out) from a dead spot in a faulty ignition switch when turning the key from run to crank.

[Stalls]

Here is the theft data... Notice the data changes with key on vs off... That is why there is 2 screen shots of the same data...

[Stalls]

UPDATE!! I replaced the ecu and did a relearn on the theft deterrent module and it cranks now! But no fuel... Currently checking...

[Stalls]

Another update!! Sorry a lil late cuz I forgot... I got it to start and run!!! I checked out some wiring and found it also has a bad fpcm. I couldn't get a used one tonight cuz it was to late but I did rig it to run the pump and it started and ran great! Now for all the other lil things to fix...

Also I am fixing the cluster myself.. I found that the communication chip is burned up. So I will solder in a new one. Should be good to go on that end as well..

[ToltecasChavez]

Glad you sorted it out man! Let us know how it goes.

[Stalls]

I got the instrument panel cluster fixed by soldering in a new communication chip. The fuel pump control module should be here in a few hours. So that should take care of this thing starting under its own power.

I wonder if this thing was struck by lighting? I have never replaced so many modules on one vehicle before. So far that is a total of 6 as far as I can remember lol... All were legitimately bad as in not working at all and disrupting the can bus line. Or working (like the ecu and fuel pump control module) but not working quite properly. Who knows there might be a few more.....

[Witsend]

Wow, soldering in new communication chip ? Where can you get replacements locally? I think you can get many kinds of electronic components from Digikey, but probably not from parts stores or GM. Guessing you get the donor for the original cluster from off the used cluster?

[Stalls]

Yes I borrowed another chip from a another module. They kinda use some of the same chips. I like to tear apart clusters and other parts to fix the overall part instead of buying a whole new one.

Update again.. I got the fuel pump control module and it starts and runs under its own power now! I still have quite a few other lil problems though to fix though lol. I am almost certain this vehicle has been hit by lightning or something similar?