Bmcghan09

It is just a little plastic piece that runs a harness over the ground. I’m sure it’ll be fine. Probably just for assembly/ rubbing reasons.

Well taking the dash apart was very fast and easy less than 5 minutes. Now getting to the ground is another story it’s in an awful spot and but I finally got to it. And yup the plastic was pinched right there. I had to use a shallow well 10mm a universal and a few extensions but I got it off and trimmed. I’m just realizing I forgot to put a harness clip back on that ground but oh well.

I wont know, It happened a couple times like 5 weeks ago on a Saturday dealer had it for a few days couldn't make it do it again and then 4 weeks later it did it and wouldn't start for like 15 hours. Tried it once in the morning then one more time an hour later and its been fine since. It hasn't done it to me since friday night, I had it towed home because I knew it would start. I just cleaned up the ground tuesday and I guess we wont know for a while.

Yes from the battery it is only two grounds, one to the frame and one to the engine. Engine looked to be fine. G141 on mine was pretty nasty. I bet only half the terminal was contacting. Lots of undercoat under it and some corrosion. I tightened it up pretty good. It's still on my list to add a ground from the battery over to the break booster. This would put a direct BCM ground less than 12" from the battery ground. I assume the bad fastener does stretch and allows the terminal to back away.

This is a good read!

I'll pull the dash one G218 this week or weekend. looks to be like a 10 minute job to get to it.

This ground is in the passenger side wheel well. You do not need to remove the fender liner to get to it. I used a wire wheel and adhesive remover. I cleaned it up pretty well when I was done. But you can see that something may have been going on with the ground itself. The other runs to the back of the engine block and looked fine. I may do what someone else did and add another ground to to brake booster. I have not pulled the dash apart yet for the BCM ground. That will be my next step.

Alright. So I couldn’t do my push to start last night. The screw on the terminal was so rusted it was going to break off the terminal so I didn’t go for it. I took the wheel off the fender flare and the fender liner. The command terminal on the starter solenoid wiggles a bit so I wonder if something internally is broken. I ran a zip tie to hold it tight for now, if it holds. The starter looks like a massive pain in the ass to do. What I did find was a rough looking main ground from the batteryZ the rubber coating came down half the terminal I circled how far it came down and then there was a ton of under coating under the terminal itself. I took a pic half way through cleaning the ground up. The red circle is how far the wire coating covered up the terminal.

I haven't found a chaffed wire yet. I will be looking while I'm under it today wiring up my power probe (redneck push button start).

Yeah I have no warranty for anything electrical. I will be looking at all of the grounds and power when I'm under it hooking up my redneck push button start.

Comedic update: I am going to start chasing down all of the grounds off the battery cable and the BCM ground. under the dash. Battery tested good. I was just making a joke about the quality control to my buddy who has friends who work for gm. My joke was they have half blind people doing these grounds... And guess what? His buddy is 50% blind in one eye.... Had a B1325 HVAC control power voltage below threshold Cleared it and got back today U0020 slow CAN Bus History HVAC.

So all I've done is read and read about this. TONS of people had starter issues same issue and ended up being a poorly designed starter. I told Tbarn to go kick rocks (so to speak) when he just said throw a starter in it. And then the other guy saying put a battery in it.. The dealer said there was not signal going to the starter and I'm doubting them now. I put factory 2825 bulbs in and cleared all the codes. The burnt out bulb or LED light WILL throw a BCM short code! One code came back as history and I cleared it again. Now there's no codes anywhere. So this is my plan, I'm going to go buy a manual horn button the large contact style and run a power to the starter solenoid. Ill zip tie it to the battery bracket. If it does it again I go out and hit my redneck push to start and see if it cranks, If it does then I turn the key and try to see if cranking actually starts it. That will rule out these issues. Also while I'm there I'm going to run the battery tester a few times. I guess if the system even detects a slight change or drop in the voltage it will not send the start signal. Edit here's the link about the starter issues

Yeah, it’s insane there’s no limp mode or anything. Im disappointed in the engineering. Only good news is I think it’s the back harness. I’d rather pull that harness vs the front. The dealer said that even a little bit of feedback will shut down the module.

It seems LED bulbs are a toss up. I think quality of the bulbs matters as well. I’m currently riding dirty and don’t have any bulbs in. I was afraid to touch it. My entire truck was switched over to LED by the previous owner. My license plate screws touch the harness so I’ll pull that down when I get time. There’s no fuse either. Seems like they are part of the BCM circuit which doesn’t help much.

Update: I think I have it narrowed down to a short in the license plate circuit. Just happened to me again last night and wouldn’t start for about 12 hours. I have a super super nice scan tool with me now and it read short to battery license plate. I think that is what back fed and shut down the CCM. Because they are all right there. Going to pull the harness down soon.

Actually starter is fine. The command to start never made it to the starter... We could see and even I could see that. The dealer could see that the start command was not sent to the starter. It ended at the BCM due to a fault............ My post states signal was not getting to the starter as well..

Probably should put a transmission too huh?

1GTV2UEH7EZ100315 I think its AUG. but I will look into this!!

I really doubt its a bad battery. The battery looks brand new and there's no other issues. 9* outside and started fine. This truck is CLEAN crazy clean frame too. No rust anywhere. This spring I'll spend a day pulling the harness and checking for peace of mind.

This is super interesting. If I start pulling more codes I may touch base with you and dig further.

Anything U coded is Electrical. They are most defiantly real, and they are a real pain in the ass.

The paper from the dealer said U0140 loss hvac loss to BCM but, noted for future reference. I'll have to see if my buddy can scan it with his scan tool. Mine only pulls engine, ABS and SRS

Well, at first it was "license plate bracket" and circuit had feed back and was interrupting the BCM/CCM. So I pulled the LED lights at their recommendation, I did not have the code for that. For those asking about LED lights, this model and up the electrical system measures the resistance of ALL the circuits. When not equipped with factory LED and you switch over it can cause "feedback" or resistance issues. I've heard of this before but with the quality of GM and all the electrical issues the LED lights carry no resistance compared to your normal bulb, therefore there can be power to other grounds in the system. But back to my truck, after the initial license plate bracket feed back issue I pulled the bulbs and it wouldn't start. Then we got a ccm communication issue, not communicating at all (I don't have the code for that). The following day the truck was starting great but pulled a HVAC communication code U0140, the controls worked fine. Today the truck is working fine. I personally think there's a ground issue or something shorting and feeding power to the grounds of the truck. I live here in Lansing MI where there is a ton of GM plants and suppliers. If I told you the personal first hand stories I have heard about quality control issues you guys would freak. I've had newer Fords for the last 8 years and never had any of these issues. I loved the look of the GM and was trying to save a little money as I just bought a house. The fords are priced higher so I gambled with the GM. If this does it again and the dealer cannot figure it out, I am going to go attempt to "tune and delete" what I can so the drive-ability is basically standalone relying on the ECM only. I love the look of the truck and it seemed finally GM stepped up their build quality but it appears to be the appearance only. My background, I used to be a certified technician (Not GM factory trained). I've tuned and ran stand-alone ECM's for older 1st-2nd gen 5.3s.

I just bought a 2014 Sierra 1500 Z71 double cab with 95.000 miles. Saturday I went to get my hair cut and after got in my truck to leave. It wouldn't start. I keep a scan tool on me so I scanned it and no codes. Everything would turn on and work just no signal to the starter. I call onstar for towing and I'm sitting there randomly trying to start it. Putting it in neutral, cycling the locks all the old tricks. I open the hood, check the cables and everything is fine. Go to start it and boom started right up. I drive right to the only dealer who's open and they determined it was the license plate LED lights and they should be normal lights. Dealer tells me that's all and sends me on my way. I go to start it to leave and once again it wont start. They scan it again and determine the chassis control module was not communicating for some unknown reason. I leave it there and all day yesterday and today its been starting just fine. So I guess I am going to pick it up tonight. I don't like the idea of rolling the dice every time I go to start my truck. Anyone experience this or have an idea? Dealer is clueless.