TCM died. Can't program the new one with tech 2

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ahunn

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So I was driving and suddenly the tahoe bogs down. Stopped shifting and I noticed I had to rev it higher to get it to move. I got nervous of course and pulled over to the side of the road. I noticed that I could no longer tell that I was in drive nor any other gear on the prndl. I decided to check the transmission temp and nothing was showing there either.

When I made it home I connected my tech 2 and found that the tcm wasn't communicating. Apparently they can die just like that without any warning..?

I bought a new tcm module from the dealership for 101$. Tried to program the new one with the tech 2 but it fails at 80% when installing the calibrations. I can't figure out what the heck is wrong. I've never had issues programming before. Anyone have any idea what could cause it not to work?
 
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Doubeleive

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So I was driving and suddenly the tahoe bogs down. Stopped shifting and I had to rev it higher to get it to move. I noticed that I could no longer tell that I was in drive nor any other gear on the prndl.
I connected my tech 2 when I could and found that the tcm wasn't communicating. Apparently they can die just like that without any warning.

I bought a new tcm module from the dealership for 101$. Tried to program the new one with the tech 2 but it fails at 80% when installing the calibrations. I can't figure out what the heck is wrong.
I've never had issues programming before. Anyone have any idea what could cause it not to work?
poor connection, low voltage or both
I would suggest disassembling all connections on the tech2 (blow them all out with air) and reconnect tight and snug
blow air in the obd port as well
have the vehicle on a battery charger while programming
plug the tech2 into 12dc (wall outlet) this should be plugged in on the bottom of the tech2 not on the cable anywhere rather than powered via the vehicle.
then check the transmission harness disconnect and reconnect be sure it's clean as well
then try again.
 

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I would have started by verifying that the TCM is getting reference signal, and is powered.
 

swathdiver

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So I was driving and suddenly the tahoe bogs down. Stopped shifting and I noticed I had to rev it higher to get it to move. I got nervous of course and pulled over to the side of the road. I noticed that I could no longer tell that I was in drive nor any other gear on the prndl. I decided to check the transmission temp and nothing was showing there either.

When I made it home I connected my tech 2 and found that the tcm wasn't communicating. Apparently they can die just like that without any warning..?

I bought a new tcm module from the dealership for 101$. Tried to program the new one with the tech 2 but it fails at 80% when installing the calibrations. I can't figure out what the heck is wrong. I've never had issues programming before. Anyone have any idea what could cause it not to work?
I think the new way of programming is only by using the Tech-2 as a pass-thru device.

@Joseph Garcia
 

Joseph Garcia

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Yes. the Tech 2 can only be used as a pass-thru device when programming through Techline Connect.
 
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ahunn

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Sorry for getting back to you guys so late. Work got busy and I'm just now able to get online and read all of the responses.

Since i couldnt program the tcm I tried to program the driver door module just to see if it worked, and, I had an updated calibration, but it failed. I decided to go to the dealership to get it programmed. They were all days or more out for getting me in to program it and I need to work. Eventually I found a place.
There is a shop pretty much right across the street from me called Flashmasters in Cincinnati, ohio that had a tcm, and programmed it for 79$ same day. 86$ total out the door. Their focus is on all gm engine computers, some Ford also. They have a website in case anyone is interested. Anywho I thought that was a great deal and I'm now back in business.
 
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ahunn

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poor connection, low voltage or both
I would suggest disassembling all connections on the tech2 (blow them all out with air) and reconnect tight and snug
blow air in the obd port as well
have the vehicle on a battery charger while programming
plug the tech2 into 12dc (wall outlet) this should be plugged in on the bottom of the tech2 not on the cable anywhere rather than powered via the vehicle.
then check the transmission harness disconnect and reconnect be sure it's clean as well
then try again.
I had checked the harness and blew out the connector and obd port. It was actually really clean already. My voltage was good 15v, and I had the cigarette lighter connector plugged up to the tech 2. It was plugged in at the connector before the candi module.
 
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ahunn

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Yes. the Tech 2 can only be used as a pass-thru device when programming through Techline Connect.
Can you explain how this works? I actually spent the 40$ to get the tech line subscription but couldn't get the tech2 to work with it. The program kept asking me for a mdi or mdi2, or the j2534 devices which I am unfamiliar with.
 

swathdiver

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How do you use it as a pass thru device? I had it connected to a windows 7 laptop, with the keyspan USB to serial adapter.

When programming, the Tech-2 is connected on one end to the truck and the other end to a laptop which is connected to ACDelco. In the old days, I would download the program to the Tech-2, disconnect from the laptop and walk over to the car and complete the programming. It is my understanding that this latter option has been done away with.

Can you explain how this works? I actually spent the 40$ to get the tech line subscription but couldn't get the tech2 to work with it. The program kept asking me for a mdi or mdi2, or the j2534 devices which I am unfamiliar with.
Joe can explain it better than I. @Joseph Garcia
 

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Can you explain how this works? I actually spent the 40$ to get the tech line subscription but couldn't get the tech2 to work with it. The program kept asking me for a mdi or mdi2, or the j2534 devices which I am unfamiliar with.
The tech2 is a J2534 device, that is how it functions as a pass thru
 

Fless

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@Joseph Garcia wrote up an excellent guide here:


See if it has what you need to connect.
 
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ahunn

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@Joseph Garcia wrote up an excellent guide here:


See if it has what you need to connect.
Thank you. I'll check that out shortly
 
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ahunn

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Thank you. I'll check that out shortly
After reading through his post, I did everything the way he did but it looks like there is a restriction with using a tech2 to program with techline. I'll wait to see if that changes or buy a vcxnano if needed. Thank you for the link to his writeup
 
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ahunn

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I forgot to mention that after I put the new tcm module in, I was able to program other modules. Is that weird.. Could the tcm from the dealer have been defective and caused me not to be able to program other modules?

Also, I started getting c0561 symptom 71 in the tech 2. The traction control, abs, and stabiltrack lights kept coming on. When this happened, my tahoe would jerk randomly when shifting from 1st to 2nd and that was driving me crazy.
I actually corrected that issue it seems by flashing my ecm with an update as well as the ebcm and then tccm (All of those modules were a few calibrations behind so i figured id go for it). I assume the ebcm getting flashed was the cure?? It's been a full day now since flashing the modules and no more issues with the car jerking (knock on wood)
 

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