2016 LML intermittent gauge loss and no crank, no start

[Ggossett08]

2016 LML will randomly lose almost all of the gauges, does not show what gear it is in and says service stabilitrak, service 4wd, service power steering, and service trailer system. Most of the time this condition lasts 30 seconds while driving, it will not shut off, but it does shift rough when it does it. If you shut the truck off while it is doing this, it will not start back until it decides to? Also, it's rare, but it will not crank and it doesn't show what gear it is in. All of these conditions only seem to happen when its +35 degrees and below. I put several miles on it in warmer weather without issue. I have attached pictures of the codes.

Any help would be appreciated.

 

[zakkb787]

How old are the batteries

 

[Ggossett08]

I’m honestly not sure, but I had them checked. They said they were fine. It never cranks slow

 

[zakkb787]

I’m honestly not sure, but I had them checked. They said they were fine. It never cranks slow

Thats where I’d start. Even if they check fine. These trucks are notorious for batteries testing good but still causing issues especially at startup. Even if they check out fine and it doesn’t crank slow any fluctuation in voltage they’re very sensitive to.

 

[Ggossett08]

What do you think about the gauge loss driving down the road?

Under normal conditions the 5v reference high speed wires read 2.6-2.7 and 2.3-2.4. When it acts up, they read 2.9 and 1.9-1.2.0. I just can't get it to act up long enough to unplug modules until the voltages read normal.

 

[zakkb787]

It’s definitely strange. The batteries are a good and relatively cheap and easy thing to try first. I’d also check all your grounds as well and make sure they are tight and clean.

 

[Ron Nielson]

You have a circuit problem somewhere. Definitely not easy to find unless you can get your truck to exhibit the problem while you are troubleshooting. Shaking the harness underhood going to the Instrument panel would be the first thing, then maybe the TCM to trans harness would be another, then ..... who knows. Wires, especially thin wires, can break inside their insulation and it is so hard to see or locate. Do you have any codes or inability to communicate with any module via the DLC??

 

[Stingpuller]

I have a 16 at the shop now doing the same thing. hopefully i can dig into it soon. I hate electrical problems.

 

[S Phinney]

When it does this try to communicate with ecm,tcm and glow plug control module and see if it will recognize each.


Sent from my iPhone using Tapatalk

 

[036.6turbo]

You're definitely on a "bug hunt".

Known issues on these;
1. As has been stated Batteries. These trucks do very strange things when the batteries get weak. Find a buddy with the same truck, swap batteries with him for a few days, see if it helps.
2. The under hood fuse box will short out. Seen it on (3) trucks now.
3. There's a ground strap under the dash cover, up near the windshield. Seen those loose on a couple occasions, that will cause goofy things as well.

Like I said, bug hunt.