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GMT3 not remote starting

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2015 GMC Silverado 2500HD. GMT3 module, programmed correctly, A8 wire is grounded. Vehicle will not start and no lights on module when pressing the LOCK button on my factory remote.
asked Dec 12, 2019 in GMC by Eric Williams (130 points)

1 Answer

+1 vote
"A8 wire is grounded."  - This is your first problem. It will never start with this wire grounded.


-2nd, what is the service number or S/N to the module? I will check to see if your options are set up correctly.
answered Dec 12, 2019 by derek ! (277,310 points)
SN of unit is 001a07051966. I only grounded A8 because that is what i have read on other customers issues.

Do not ground the A8 wire. 

Remove it and try the remote starter. 


If it doesnt start I suggest performing a master reset (https://fortin.ca/en/download/61931/61931.pdf)


Then re programing the module from A-Z meaning options and dcryptor as well. 

A8 wire removed from ground, reset unit. When i get to step 9 when I have to wait for the blue LED to flash rapidly before I turn the key off, I have waited more then 15 minutes and the blue LED never flashes.
update - still havent gone thru the programming. hung up on step 9. however, when connected, i press the lock 3x on the OEM remote and nothing happens. but when i connect the yellow/black stipe wire to ground, the lights flash but the truck does not attempt to start. it seems like it tries 2 or 3 times before stopping.
no point in trying to remote start if the module did not even program yet.


If stuck at step 9 and that the blue led does not flash, check your CAN-SW connection. Blue light is CAN programming.
according to my install guide, the light blue gets tied to the light blue/black stripe which it is. how long does it take to get the key to program? Is waiting 15 mins to get the blue light to flash rapidly not long enough?


Also, in the contact us section, it says support hours are till 20:00 EST monday-friday. I called at 18:00 EST last night and it said they were closed. :(
tech support is open until 8 to support bussinesses/shops and the direct distributors.


Blue light not flashing = CAN-SW problem. That's the BROWN wire from the 5 pin white connector that is connected at Pin 1 of your OBD connector. If you have a t-tap/posi-tap on this, remove it and do a proper splice connection.
Everything is connected per the instructions. When programming I get to step 9 and it gives me a flashing yellow and red light. What does that mean? Is there a list of troubleshooting lights that I can have? Going back to this forum is very irritating. Been going on for a week now. I am ready to return this product because it is not working.
Sometimes I get to step 9 and it goes through the flashing sequence but after flashing yellow it goes solid blue. Someone please help before I return this product

The initial problem was that A8 was grounded. This makes the evo think the hood is open and prevents remote start. You didnt have to reprogram the unit afterwards, Once it's programmed, it's programmed. Even if disconnected for 20 years.  


Looking at the flash history, at some point you managed to run through dcryptor 4 different times successfully. What changed??? 


  1. RESET the EVO: https://fortin.ca/en/qa/50193/faq-how-do-i-reset-my-evo-all?show=50193#q50193
  2. Enable option C1 + D1 (do not turn touch any other option)
  3. Plug in only the RED connector and start the car once. Shut car down and leave the RED connector connected. 
  4. Attempt to program EVO.


You will also need to take out your meter and test some wires. 

YELLOW wire on 20-pin = ignition (0V key off, 12V key on)

---- If you get no reading, check fuse labeled Discret Logic Ignition Switch (DLIS)


BROWN wire from 5-pin = CAN-SW (key ON should read a couple volts DC)

--- no reading = connection problem.


If you still cannot get it to work, I can only suggest simply having a remote start installed by local professional. 



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