No crank no start

[Crazy Jake]

My 2018 6.2L yukon denali suddenly won't crank. When I push the button with the brake depressed, the dash blanks out and the entire system reboots. It will go into accessory mode just fine and all the electronics work. I scanned and there were no codes. This problem happened suddenly without any indication. I removed the negative cable, let it sit for a few minutes and no change. I tried to use a jumper pack, had good voltage but no change to the problem

 

[Doubeleive]

you'll have troubleshoot a little more.
check BOTH battery cables make sure they are clean, wire brush even if they"look" ok
then use a meter and see what the resting voltage is, and what it is while the start button is depressed. 10.5v is the bare minimum.
if that is all good, check starter relay, you can jump the relay and see if the starter turns.
if not then proceed to check voltage and ground at starter, if you have a minimum of 10.5v at starter (when attempting to start) and nothing happens, then pull starter and bench test.
another thing you can try also is there is a know issue with the steering wheel position and push to start. try turning the steering wheel back and forth a few times and try again.
if turning the steering wheel works you will want to take it in to the dealer for either a software update/recalibration or they may recommend a part

 

[homesick]

you'll have troubleshoot a little more.
check BOTH battery cables make sure they are clean, wire brush even if they"look" ok
then use a meter and see what the resting voltage is, and what it is while the start button is depressed. 10.5v is the bare minimum.
if that is all good, check starter relay, you can jump the relay and see if the starter turns.
if not then proceed to check voltage and ground at starter, if you have a minimum of 10.5v at starter (when attempting to start) and nothing happens, then pull starter and bench test.
another thing you can try also is there is a know issue with the steering wheel position and push to start. try turning the steering wheel back and forth a few times and try again.
if turning the steering wheel works you will want to take it in to the dealer for either a software update/recalibration or they may recommend a part

Based on my own recent experience, I'd add a recommendation to remove both cables from the battery and brush all the contact areas too; even if they look good, as doubelieve said.

joe

 

[Crazy Jake]

All grounds and power connections are good to the starter and starting voltage is good. Going through some of the fuses, i can definitely tell it has had this problem before, i just don't have the systems knowledge on this vehicle to start diagnosis outside of checking fuses and connections. I wish it would throw a code

 

[Hank357]

I have a 2017 6.2L Yukon Denali and I'm currently having the same problem. I took my truck to the dealership last month and they replaced both battery cables. That worked for 41 days, and the problem started again. The dealership service guy said my engine fuse box was bad and I had that replaced. They got the vehicle running but when I went to pick up my truck Wednesday it did the same thing and will not start. It's been a week, and they are still trying to figure it out. Does anyone have any suggestions on what the problem could be?

 

[Crazy Jake]

I have a 2017 6.2L Yukon Denali and I'm currently having the same problem. I took my truck to the dealership last month and they replaced both battery cables. That worked for 41 days, and the problem started again. The dealership service guy said my engine fuse box was bad and I had that replaced. They got the vehicle running but when I went to pick up my truck Wednesday it did the same thing and will not start. It's been a week, and they are still trying to figure it out. Does anyone have any suggestions on what the problem could be?

Do you have any issues with your electric seats not adjusting and loosing their memory? When that happens to me, I bang on the drivers side fuse box and it starts working again. I'm wondering if the two are related

 

[Hank357]

I haven't any issues with my electric seats or their memory.

 

[Doubeleive]

like I told the op it takes more troubleshooting, when the no crank happens the first place to check is the voltage then the starter, then work backwards.
jump the relay, if nothing happens check the voltage at the starter, if voltage is good pull starter and bench test, if voltage is no good check battery/cables/grounds.
if voltage is good and starter works when jumpered then check between starter relay and ignition.
it's a process of elimination
***if banging on the fuse box fixes the issue there is your clue, fuse box, fuses, wiring at fuse box.............................................

 

[Hank357]

I just spoke with service guy at the dealership, and they seem to have things in order. They ran a current draw test twice already and my truck passed. He is running the test again today just to be safe. Mr. Doubeleive is correct about troubleshooting. The troubleshooting will take some time, but you will get to the root of the problem. Once, I get the final write up from the dealership. I'll post all the things they done to get my truck back running.

 

[Hank357]

I got my truck back yesterday fellas. Here's what the dealership service department done to get me going.

1. Checked and tested battery cables. Had a high resistance on cables. Replaced both battery cables.
2. Checked battery fuse block and its good.
Checked underhood fuse block and some fuses had low voltage. Internal fuse block problem.
3. Replaced fuse block, rechecked and now has proper voltage
4. checked and recharged the battery and performed current draw test over a few days and there was no abnormal draw.

I was out of $1,800 but it got me back on the road. The fuse block comes with a 2yr warranty with no mile's limit.

 

[LsHart]

Wire brush on some fuses was all you needed. Dang.