ECM VATS Relearn:

McRat

McRat

Diesel Hotrodder
Aug 2, 2006
11,249
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Norco CA
www.mcratracing.com
When you switch ECM's, your truck probably will crank, but won't start.

Here's how you "teach" the truck your new ECM:

Turn ignition on
Try to start (it won't)
Leave ignition on.
In 10 minutes exactly the SECURITY (lock) light will turn off.
Try to start (it won't)
Leave ignition on.
In 10 minutes exactly the SECURITY (lock) light will turn off.
Try to start (it won't)
Leave ignition on.

In 10 minutes, the light will go out, and it will start up, and will "marry" the ECM to the BCM permanently.

This will even work with locked "pre-programmed" ECM's so you can test them on other trucks.

I'm pretty sure I've posted this before, but just in case, I posted it again.
 
C

Cougar281

Well-known member
Sep 11, 2006
1,820
259
83
St Louis, MO
OR.... Fire up your scan tool, connect to the ECM, activate DVT select "Learn Now" under "VATs Relearn". :D

If for some reason that doesn't work, and you need to go through the long relearn process and can flash your ECM, go to G0302, change it from 600 seconds (10 minutes) to 10 seconds, so it'll be:
Turn ignition on
Try to start (it won't)
Leave ignition on.
In 10 seconds exactly the SECURITY (lock) light will turn off.
Try to start (it won't)
Leave ignition on.
In 10 seconds exactly the SECURITY (lock) light will turn off.
Try to start (it won't)
Leave ignition on.

In 10 seconds, the light will go out, and it will start up, and will "marry" the ECM to the BCM permanently.
 
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LarryJewell

LarryJewell

Back with his honey :)
Jan 21, 2007
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San Angelo
Cougar281 said:
OR.... Fire up your scan tool, connect to the ECM, activate DVT select "Learn Now" under "VATs Relearn". :D

If for some reason that doesn't work, and you need to go through the long relearn process and can flash your ECM, go to G0302, change it from 600 seconds (10 minutes) to 10 seconds, so it'll be:Turn ignition on
Try to start (it won't)
Leave ignition on.
In 10 seconds exactly the SECURITY (lock) light will turn off.
Try to start (it won't)
Leave ignition on.
In 10 seconds exactly the SECURITY (lock) light will turn off.
Try to start (it won't)
Leave ignition on.

In 10 seconds, the light will go out, and it will start up, and will "marry" the ECM to the BCM permanently.
Click to expand...

So I assume your referring to changing this within a tune and flash this tune to your ecm :confused:

If you have access to a tech 2 can you get around all this stuff:confused:
 
L

LLYDuramax

New member
Dec 29, 2009
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Portland,ME
So I need some help, My Scan tool VATS Relearn wont connect so i tried doing it the normal way. But When I do the Key cycling. After I do the first crank then let it sit for 10 minutes and the light goes out. I crank again and the light stays on for only a few seconds and goes out?? and it still wont start? anyone have a similar issue or an idea?

Thanks,Ethan
 
chevyburnout1

chevyburnout1

Fixing it till it breaks
Aug 25, 2008
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Berthoud, CO
You have to do that procedure two more times. As in crank it then wait 10 minutes. Once light is out turn the key off for 5 seconds. Then crank engine, wait ten minutes. Key off 5 seconds. Crank again and wait 10 minutes. Off 5 seconds. Then turn to crank and engine should start and theft key relearned.
 
T

Truckcave

New member
Apr 23, 2013
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1953drtelco said:
I tried this procedure on a locked ECM and it worked....great info to keep on hand
Click to expand...


Wait.. so this works on any "locked" ECM?


Long story short...

Tried using a 2nd-hand VIN-locked QS2 on my LB7. Didn't work. Accidently did the "Reset to Stock" option, which I believe flashed previous owners stock info onto my ECM. Truck would CRANK, but not start. Tried to load a new 50HP tune, it took after several tries, truck still won't start. Now all I get is "No connection" or "Error".

Towed to dealer, they couldn't reflash, wanted me to pay 2k for a new ECM...

Bought a reman ECM from Rob with EFI Live, was going to install when it arrives in a day or so... Was researching this VATS relearn so I could how to install it.


IS IT POSSIBLE that all I need to do with my current "locked" ECM is this procedure? Is my ECM "locked," if it won't take a reflash, or actually damaged... Any comments would be welcome. It can't hurt to try.
 
C

Cougar281

Well-known member
Sep 11, 2006
1,820
259
83
St Louis, MO
It's for when you install a new ECM in your vehicle (or for some reason your current ECM's VAL link breaks) and have to re-link VATS. Wheather or not the ECM is locked with a custom tune is irrelevant.

As for your issue with the QS2, yes, it sounds like it at least tried to flash your ECM with the previous owners stock tune. I can't comment on what the dealer really found, but I'd think it would be able to be flashed with your stock tune... I doubt very much that this procedure would do anything with your original ECM. It could be smoked, or there may be a way to reflash it that the dealer didn't try.
 
quinton

quinton

Active member
Nov 28, 2011
1,883
0
36
Granbury Tx.
Truckcave said:
Wait.. so this works on any "locked" ECM?


Long story short...

Tried using a 2nd-hand VIN-locked QS2 on my LB7. Didn't work. Accidently did the "Reset to Stock" option, which I believe flashed previous owners stock info onto my ECM. Truck would CRANK, but not start. Tried to load a new 50HP tune, it took after several tries, truck still won't start. Now all I get is "No connection" or "Error".

Towed to dealer, they couldn't reflash, wanted me to pay 2k for a new ECM...

Bought a reman ECM from Rob with EFI Live, was going to install when it arrives in a day or so... Was researching this VATS relearn so I could how to install it.


IS IT POSSIBLE that all I need to do with my current "locked" ECM is this procedure? Is my ECM "locked," if it won't take a reflash, or actually damaged... Any comments would be welcome. It can't hurt to try.
Click to expand...

You are screwed. Need a new ECM or send yours off to be tore apart.
 
T

Truckcave

New member
Apr 23, 2013
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Made an attempt.. The battery is running low so I need to charge it seperately before I install my new ECM.

When turned to on, the fuel gauage is not reading... and the security light does not remain on.. the battery light just flashes. Also Wait to Start does not display... This is obviously not what I should be seeing if a VATS is all thats required, so I didn't continue any further.

Will try from scratch with Robs ECM as soon as it arrives. Thanks.
 
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D

diesel vein

New member
Apr 2, 2011
15
1
3
My truck is an 04.ecm is locked.v2 won't pick it up.i tried about ten times to get the v2 to read the computer and bam it won't turn over.what could be the problem?
 
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