Hit Paydirt at Pick-n-pull today

[Capt_Caveman]

So Omar, Care to offer some more help?

I made some phone calls over lunch today to the local dealers. The best response I could get was that they could try to enable the BCM but could not guarantee it would programmable. One dealer shop foreman said he has been in the biz for 30 years and never heard of being able to do it. Another said the BCM does not get programmed but the heated seat module does. (if this was the case, why wouldn't one that was already working continue to work?)

Anyway, these responses did not garner much confidence so I ran down to the yard after work and pulled the BCM from the junker. Only cost me $5.00 so I can't complain. If I have to get the radio cleared again so be it. I'd have to spend the $$$ anyway so at least I should know the seats are working.

Back to the point, Do you have the instructions to install the BCM that you referred to?

TIA

 

[OmarR]

http://www.tahoeyukonforum.com/forum/showthread.php?t=19467

 

[Capt_Caveman]

http://www.tahoeyukonforum.com/forum/showthread.php?t=19467

thanks. I think I'll give the BCM swap a try as see how it works.

 

[Capt_Caveman]

Wellllll, I'm a 1/2 step closer I think. I'm starting to feel like a detective. Beat the bushes, pick up clues .. instead of 'who done it' it's 'how's it done'? (But I Digress)

First off, I found an old thread on a truck forum discussing adding heated memory seats. What I found interesting was that in this case, once the owner performed a Memory Seat Calibration procedure the heated seats worked but he still needed the BCM changes for the memory option.

So I put the Z71 BCM in the Tahoe to see what happens. (also did the memory seat calibration procedure) Still no heated seats but the memory buttons worked immediately. The outside mirrors moved using the memory button but interestingly, the seats did not move at all.

I'm thinking I either have the wiring incorrect/missing or I'm missing a relay somewhere. I'm leaning toward the seat module not communicating with the GMLAN but a missing relay is still a possibility. I put the original BCM back in for now till I figure out the wiring. At least I didn't spend any $$$ at the dealer yet.

 

[OmarR]

I wish I could offer further help, but at this point, you have surpassed me in this specific mod/upgrade.

I will take a look at the wiring diagrams in my shop manual to see if I can spot anything.

 

[Rivieraracing]

I wish I could offer further help, but at this point, you have surpassed me in this specific mod/upgrade.

I will take a look at the wiring diagrams in my shop manual to see if I can spot anything.

Never would have thought I'd ever see those words come from your computer keyboard OmarR!! lol

If you couldn't tell already Capt, OmarR is our version of the Chevy/GMC whisperer!! He's the man when it comes to ultimate knowledge of our trucks, and if he doesn't know something then you are truly pioneering something awesome!!

 

[Capt_Caveman]

Ahhhhhhhh .. the sweet Warm feel of SUCCESS!!!!!

I guessed right about the seat module not communicating on the GMLAN. When I wired the harness, I had a brown/white wire that I was not sure about. Originally I thought it just grounded to the body then I traced it to an unused connector in the pillar between the doors. The other day I found a connector schematic that showed the data wire as brown/white wire so I figured it was worth a try. I didn't feel like removing everything and trying and find a data wire in the body harness. Since I just upgraded to the NAV radio and a 6CD changer, I knew right where to find the data wire in the console. I connected the seat to the data wire and VIOLA! heated seats.

For anyone interested, you do NOT need to have the BCM flashed or swapped for the heated seats to work. However, if you want the memory feature for the seats and mirrors, then it will require the BCM to be updated or swapped for one with that option.

I have the other BCM but the memory feature is not important enough to spend $$$ at the dealer to get the radio unlocked again. Who knows, I may change my mind at some point and go for the memory features.

 

[Rivieraracing]

That's awesome Steve, congrats!!

 

[Capt_Caveman]

Addendum: you know the saying, 'no good deed goes unpunished' ... On my way home from work last night I was assaulted by [FONT=&quot]kamikaze[/FONT] deer. 1/4 mile from home, straight road, open fields on both sides and no other traffic. Blasted beast nailed me in the rear driver's quarter panel just in front of the taillight. Broke the side window, cracked the vent cap and the panel is sprung. I'll be surprised if they don't need to replace the entire quarter panel.

 

[OmarR]

Nice!

See Riviera....even I learned a little something from Capt_Caveman forging ahead with this mod. Granted, if I had more time to acquire the harness and complete this mod, I would have figured out a missing data line was my problem....but now thanks to Capt, I will be prepared whenever I find a harness.

Also learned that the BCM swap was not completely necessary, but I would have done it anyways for the complete heated seats/memory seats/memory mirrors mod. Having buttons on the door that didn't function would have bothered me.

Hey, Capt....where you located at? I want to know where your cool junkyard fiinds are at. If you frequent them and find another heated seat harness, yank it for me. If you want to make some $$$. Ha ha.