LML Electrical Issues

Vash

New member
Mar 30, 2018
2
0
0
South, Tx
Hey guys/gals, I'm new to the forum (and Diesels/Duramax/Chevy's... etc).

I'll try to be as detailed as necessary without getting to far in the weeds.

So a couple of weeks I purchased a 2015 LML, Silverado LT. It had 48k miles and was very clean. I've noticed some small electrical "funny business", but nothing too off (Bluetooth would hold the phone connection even after the truck was turned off and I exited the vehicle. Now I've had vehicles my who life with BT issues, so I thought nothing of it.)

No codes have yet been appearing.

Yesterday (3/29), I installed an AirDog lift pump and GDP EZ Lynk tuner. I have not removed any emissions equipment. But lets backup half a step...

Upon near completion of the AirDog install, I thought I had found the fuse that would turn on when the key was a the "on" position, but not cranked. Not the case, had to go with another switch (I forgot right now which it was). In doing so, the computer started going a little crazy. I received 3+ codes on the screen calling out the trailer brake system, trailer lights, "Stabilitrack"... etc. Freaked me out. To make matters worse, when I did find a switch that would only turn on with the "On" position, primed the AirDog, the engine would only crank once and then not turn over. Again, multiple codes on the dash display. I :poop: everywhere.

After calling AirDog (and the dude acting like a complete asshole at first as if I was blaming AirDog... was just looking for some help, but I understand), I resolved it was simply an electrical issue, and I needed some data to work with. Welp, I bought this fancy little EZ Lynk for this reason, just didn't think I'd need it yet. Plugged it in, the truck fired up and all was good...... :beer

Now everything seems...ok.... but when I switch tunes, sometimes.. the install may stall out and the same behavior as above... not crank, tons of codes.

Should I be worried or is this typical "modified truck" / "weekend warrior" risky business? I would like to not ruin my multi-thousand dollar new toy.

Thank you in advance for all your help and replies. Please forgive the ignorance regarding the truck as I'm a new enthusiast. I have a slightly mechanical/plant/engineering background.

Kind Regards,
Vash
 

Dozerboy

Well-known member
Jun 23, 2009
4,919
498
83
TX of course
What fuses did you try and tap into? How did you try and tap into them?

If you’re not extremely careful with aftermarket electrical Equipment on new vehicles you can cause yourself a lot of headaches.


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Vash

New member
Mar 30, 2018
2
0
0
South, Tx
I followed the instructions of the airdog, I believe it was fuse 47. This fuse was taken, so I piggy backed it with the provided "micro fuse tap" supplied by AirDog.

This is what I believe caused all the problems, however it has been acting a little funny since purchase.

It is now in a more suitable fuse location, it was an empty fuse, and I want to guess (i'll go confirm) it was fuse 27, 31 or 32. It was an empty terminal near all those in the cluster.

Maybe I caused something to happen, but I'd like to fix any relays/fuses or whatever else that may be bugging out. How would I go about diagnosing this problem? It is not throwing any codes in normal or installed tunes.
 

gmduramax

Shits broke
Jun 12, 2008
4,082
252
83
Nor cal
Maybe you stretched out the fuse holder when you used the fuse tap and now the fuse isn’t making a good connection.
 

scramHD

Member
Aug 24, 2008
112
2
18
Tx / MS / AL / MEX / FL
Check all the grounds also. I went through similar issue but also had a lost communication with abs control module. Ended up being the ground screw under drivers side door....loosened on its own. Cleaned it, tightened it...all codes gone.