Did I maybe fry my ECM or BCM??

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S33k3r

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UPDATE: I got it fixed! I don't know what the "EXACT" issue even was, but I took it to the guy who installed my engine this morning and let him look at it. He was honestly just as baffled as I was. But first thing he did was double check all the grounds, just in case anything wasn't fully tightened or something from the engine install. He hooked up his scanner to it and he was able to do FAR more than I could with my $350 Innova code reader. He was able to pull up old faults from the instrument cluster, and even faults from the OnStar module. Lol! He ended up re-flashing everything and that did the trick. Everything is now back to normal again. He even helped me finish recharging my AC system since I still had the vacuum pump ang gauges and Freon and all sitting in the back of my truck. So now I'm all set, truck running good again, and AC blowing cold again!
May I suggest naming your guy/his shop? Sounds like someone we would want to do business with. :)
 
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ScottyBoy

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May I suggest naming your guy/his shop? Sounds like someone we would want to do business with. :)
He's not an actual shop. He is just a guy who works out of his home garage/shop. He has a pretty decent sized shop behind his house, and he STAYS busy just from word of mouth referrals. The guys at O'Reilly Auto parts gave me his info when I was ordering my engine. O'Reilly was one of the few local places who could get me a crate engine, pretty much EVERYONE else was on backorder with no definite expected ship date. Pretty much ALL the guys at O'Reilly vouched for him, they all said they knew him well and that he does good work and for reasonable prices.
And as far as what kind of scanner he has, I will have to ask him. I think it was an Autel, but I'll have to ask him for the model number and all.
 

iamdub

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Sounds like me- shop behind the house, word-of-mouth referrals, personal relationships with the O'Reilly guys and all! I don't have that nice of a scan tool. It is a decent Autel, though. It's about their best one-way model, but still a one-way.

Also, coincidentally, I was in Bossier City and Shreveport today.

@ScottyBoy, I'm glad you got it fixed, and so easily/cheaply. It sounds like, for whatever reason, jumping that switch scrambled the BCM's brains. What did you jump it with- a paper clip? Maybe you were touching something metal in the engine bay at the same time? Possibly while being a little sweaty/extra conductive?
 
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MassHoe04

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UPDATE: I got it fixed! I don't know what the "EXACT" issue even was, but I took it to the guy who installed my engine this morning and let him look at it. He was honestly just as baffled as I was. But first thing he did was double check all the grounds, just in case anything wasn't fully tightened or something from the engine install. He hooked up his scanner to it and he was able to do FAR more than I could with my $350 Innova code reader. He was able to pull up old faults from the instrument cluster, and even faults from the OnStar module. Lol! He ended up re-flashing everything and that did the trick. Everything is now back to normal again. He even helped me finish recharging my AC system since I still had the vacuum pump ang gauges and Freon and all sitting in the back of my truck. So now I'm all set, truck running good again, and AC blowing cold again!
Nice to see a WIN! Awesome!!
 

petethepug

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Yes, the ability to have two way communication is key. GM is so sketchy about owners having access to their lucky charms or Tech2 capabilities that they’ve almost shot themselves in the foot.

Fortunately, the guy who invested in his programming capable Tech2 was vindicated by its little known capabilities. You got styled by someone who is having a frick’n blast with the keys to the kingdom.
 

RET423

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For posterity sake, when you need to use the AC compressor to fill an empty system (because you don't have access to an AC Machine) the way you do it is to remove the AC relay from the fuse box and jump the pins with a paper clip (usually pin 30 to pin 87), this bypasses the high and low pressure cutout switches so the compressor will run and draw in the freon; once you get enough freon in the system to keep the low pressure switch from cutting off the compressor (about 25 psi on the low side) you can remove the paper clip and reinstall the AC relay to finish charging.

Simple and safe for the system, some systems combine the high and low pressure cutout switch into one switch which means a simple jump wire replaces the expected resistance on the circuit with a dead short. There are protections that might allow the system to survive this short (sounds like yours recovered with a reset/reflash) but jumping it at the relay prevents that from happening.
 

swathdiver

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UPDATE: I got it fixed! I don't know what the "EXACT" issue even was, but I took it to the guy who installed my engine this morning and let him look at it. He was honestly just as baffled as I was. But first thing he did was double check all the grounds, just in case anything wasn't fully tightened or something from the engine install. He hooked up his scanner to it and he was able to do FAR more than I could with my $350 Innova code reader. He was able to pull up old faults from the instrument cluster, and even faults from the OnStar module. Lol! He ended up re-flashing everything and that did the trick. Everything is now back to normal again. He even helped me finish recharging my AC system since I still had the vacuum pump ang gauges and Freon and all sitting in the back of my truck. So now I'm all set, truck running good again, and AC blowing cold again!
This was a job for a Tech-2, not the Innova.
 

petethepug

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To program with a Tech2, you can longer purchase the Tech2 as a standalone device anymore.

The Tech2 software integrated into a WIN 7 or 10 laptop is needed, along with the MDI device or the VX Nano which is really finicky until you learn all the work arounds.

To program a GM device on the bench, like a BCM or other new, off the shelf device is something I have no idea on what is required.
 

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