'11 Yukon Electrical Issues

[CapnCrunch]

Hi all,
I've read some the threads that somewhat relate to my issues... mine seem much more intense.
First- vehicle is '11 Yukon SLT w/ approx 95K miles, new to us 15 months ago. Shortly after purchase @ 70k miles (and I suspect for previous owners as well, as we purchased under book value from a dealer) the electrical started acting odd. The whole dash will "flash." I use this term to describe a host of events that culminate in the same problem... sometimes it's just a seatbelt light that comes on and flashes for a second or two, to as severe as "Service stabilitrac" light coming then leaving. My wife and I have come to understand what this all means... after stopping the rig and turning the key off the entire vehicle is electrically dead-no lights, no horn... just dead (except a rapid, faint clicking noise from the driver's door) which requires simply opening the hood and lifting on the negative battery cable and putting it back... rig will start and do fine until the next episode.

To save a few posts at least, have had it into a local battery store chain, also Les Schwab, PNW tire chain w/people I've done business with for years... all say battery is good, replace battery cables. But at least at Les Schwab I was able to get the issue to duplicate w/service tech there (when event signaling event was imminent stopped in and left motor running until he came out.) He witnessed the vehicle at shutdown go dead, me touch battery cable, vehicle start and run fine... he had me shut it down, tested battery w/and w/o load... had me start again, shut it down and then he inspected and tested security of all connections (including reefing on negative cable thinking it was a loose connection) all to no issues apparent.

I seek advice as the issues this week have escalated to the point of feeling maybe it's becoming unsafe to drive... the last time something happened (yesterday) the whole dash went dead, all gauges went to zero, flashed to full as if just started, vehicle acted as if it shifted to neutral (motor revved up as if out of gear.)

One thing that is possibly more related to (noobi-ness warning!) fuel saver system that turns off 4 cylinders... vehicle surges somewhat without that system actually switching from 8 to 4 or visa versa.

I forgot to mention... other signaling symptoms are lights - sometimes dash, headlights, interior lights - varies at random.

That's my story, looking for insight from the more experienced with these modern marvels that always seem more complicated but not always for the better.

Mark

 

[swathdiver]

Hi all,
I've read some the threads that somewhat relate to my issues... mine seem much more intense.
First- vehicle is '11 Yukon SLT w/ approx 95K miles, new to us 15 months ago. Shortly after purchase @ 70k miles (and I suspect for previous owners as well, as we purchased under book value from a dealer) the electrical started acting odd. The whole dash will "flash." I use this term to describe a host of events that culminate in the same problem... sometimes it's just a seatbelt light that comes on and flashes for a second or two, to as severe as "Service stabilitrac" light coming then leaving. My wife and I have come to understand what this all means... after stopping the rig and turning the key off the entire vehicle is electrically dead-no lights, no horn... just dead (except a rapid, faint clicking noise from the driver's door) which requires simply opening the hood and lifting on the negative battery cable and putting it back... rig will start and do fine until the next episode.

To save a few posts at least, have had it into a local battery store chain, also Les Schwab, PNW tire chain w/people I've done business with for years... all say battery is good, replace battery cables. But at least at Les Schwab I was able to get the issue to duplicate w/service tech there (when event signaling event was imminent stopped in and left motor running until he came out.) He witnessed the vehicle at shutdown go dead, me touch battery cable, vehicle start and run fine... he had me shut it down, tested battery w/and w/o load... had me start again, shut it down and then he inspected and tested security of all connections (including reefing on negative cable thinking it was a loose connection) all to no issues apparent.

I seek advice as the issues this week have escalated to the point of feeling maybe it's becoming unsafe to drive... the last time something happened (yesterday) the whole dash went dead, all gauges went to zero, flashed to full as if just started, vehicle acted as if it shifted to neutral (motor revved up as if out of gear.)

One thing that is possibly more related to (noobi-ness warning!) fuel saver system that turns off 4 cylinders... vehicle surges somewhat without that system actually switching from 8 to 4 or visa versa.

I forgot to mention... other signaling symptoms are lights - sometimes dash, headlights, interior lights - varies at random.

That's my story, looking for insight from the more experienced with these modern marvels that always seem more complicated but not always for the better.

Mark

Hi Mark,

A bad cell in a battery can be hard to detect and such wreaks the kinds of havoc you are experiencing. How old is the battery? If the cables are not rotten and the battery and grounds are good, chances are the Body Control Module is in need of replacement but I'm making an educated guess from my chair and don't have my Tech-2 hooked up to your truck. Welcome to the forum by the way, nice boat!

 

[CapnCrunch]

Hi Mark,

A bad cell in a battery can be hard to detect and such wreaks the kinds of havoc you are experiencing. How old is the battery? If the cables are not rotten and the battery and grounds are good, chances are the Body Control Module is in need of replacement but I'm making an educated guess from my chair and don't have my Tech-2 hooked up to your truck. Welcome to the forum by the way, nice boat!

Hello swathdiver, thanks, we love the boat, but engine issues are preventing enjoyment currently - but that's I suspect a different forum!

Body control module... is that a common issue with these? I was told by a Les Schwab (being from Florida that company may not be familiar - think Firestone Tire Centers, but West, Midwest company, I think like 500 stores, and they don't do complete auto repair) who had a '12 Tahoe that it's a known but somewhat rare defect... she went through the same exact issues - had all battery and a harness replaced... after it still acted up she traded it off for a dodge lol.

Battery is less than 2 years old - replaced by the dealer (Northwest Motorsports, partially owned by a NW baseball legend, Jay Buhner from the Mariners) a few months b4 I purchased... I suspect because of the symptoms I'm facing.

I'll look up the how and where of that module and try it... crossing fingers!!

 

[swathdiver]

Hello swathdiver, thanks, we love the boat, but engine issues are preventing enjoyment currently - but that's I suspect a different forum!

Body control module... is that a common issue with these? I was told by a Les Schwab (being from Florida that company may not be familiar - think Firestone Tire Centers, but West, Midwest company, I think like 500 stores, and they don't do complete auto repair) who had a '12 Tahoe that it's a known but somewhat rare defect... she went through the same exact issues - had all battery and a harness replaced... after it still acted up she traded it off for a dodge lol.

Battery is less than 2 years old - replaced by the dealer (Northwest Motorsports, partially owned by a NW baseball legend, Jay Buhner from the Mariners) a few months b4 I purchased... I suspect because of the symptoms I'm facing.

I'll look up the how and where of that module and try it... crossing fingers!!

No, it's not a common part to fail but they do go bad sometimes. It has to be programmed to your VIN and is under the driver's side dash.

If you do your own work or diagnosis, a Tech-2 is indispensable, the most important tool in your kit for working on these.

 

[CapnCrunch]

Thanks muchly... is there a specific obd-2 reader you'd suggest, or will any generic do the same? I find them on Amazon ranging from +?- 60 to (gulp) 3k... and will it allow me to program to vin myself?

 

[CaptainAmerica1]

Tech2 they’re about $350 shipped

 

[CapnCrunch]

Hi again all... absent for a bit as I'm still chasing gremlins in my boat that happens to have a gm 350 tbi system (uggh)... things today soured on the Yukon, it's totally dead and no amount of tinkering brings it back. Battery charger when connected gives a green light, starts charging, there's a click that I can't locate under the hood, and battery charger shuts off w/green "good to go" light back on.

Any specific fuses maybe that might kill entire system electrical like that?

Thanks to any and all that might have a suggestion.

Gonna pull the battery tonight to get it tested in the morning, however battery has always tested (even just weeks ago) good.

 

[wsteele]

I think the only reason the charger turns off is it is sensing the battery is fully charged, none of the trucks electronics would cause it to shut off prematurely. What does a voltmeter say the battery voltage is, just after the charger is done?

 

[Doubeleive]

so... did you ever do what was initially suggested? (replace battery cables)?
you can do a draw down test on the positive battery cable, connect your meter to a good ground, touch the positive cable at the starter and have some one try to start the vehicle, if the voltage is 10.5v or less (while trying to start), replace the cable. I would also replace the ground, these cables can corrode from the inside and look perfectly normal from the outside.

 

[CapnCrunch]

so... did you ever do what was initially suggested? (replace battery cables)?
you can do a draw down test on the positive battery cable, connect your meter to a good ground, touch the positive cable at the starter and have some one try to start the vehicle, if the voltage is 10.5v or less (while trying to start), replace the cable. I would also replace the ground, these cables can corrode from the inside and look perfectly normal from the outside.

I didn't - at the time it was an irritation, and was trying to get the boat ready for an extended trip upriver. Today is when it changed for me... everything going dead with no recovery.

Today I ran across the following thread:

Complete Electrical Shutdown

I've seen posts regarding symptoms such as what I have but have not seen a resolution. I have a 2009 Tahoe 2WD LT. About once a month or less the electricla system seems to go berzerk on me. The locks cycle, the gauges go nuts and the truck will shut down. If I turn the ignition off and then...

www.tahoeyukonforum.com

seems like it's more a mfr defect that still hasn't been addressed fully. At any rate, tonight I put a new multi meter across the battery - read 4.8v while connected, 10 volts w/negative cable disconnected. Put a charger on the battery and am hoping in the morning that combined with a thorough cleaning and tightening of all connections might solve my problem... as was mentioned in noted thread above.

Mark

 

[Doubeleive]

I didn't - at the time it was an irritation, and was trying to get the boat ready for an extended trip upriver. Today is when it changed for me... everything going dead with no recovery.

Today I ran across the following thread:

Complete Electrical Shutdown

I've seen posts regarding symptoms such as what I have but have not seen a resolution. I have a 2009 Tahoe 2WD LT. About once a month or less the electricla system seems to go berzerk on me. The locks cycle, the gauges go nuts and the truck will shut down. If I turn the ignition off and then...

www.tahoeyukonforum.com

seems like it's more a mfr defect that still hasn't been addressed fully. At any rate, tonight I put a new multi meter across the battery - read 4.8v while connected, 10 volts w/negative cable disconnected. Put a charger on the battery and am hoping in the morning that combined with a thorough cleaning and tightening of all connections might solve my problem... as was mentioned in noted thread above.

Mark

those issue's were bad battery cables, it's a known problem. on a 10 year old vehicle it's kind of hard to blame the manufacture at this point. your current issue at the moment may also be related to bad cables, so bad that it's not even charging the battery properly. anything under 10.5v is a no go, I would test your battery cables, this includes the alternator charging cable and all grounds.

 

[CapnCrunch]

Update, after removing ground from battery (which tested 10.5v after that) and trickle charging all night battery shows 12.6v. Checked leads from battery to starter and to frame with both showing continuity as expected. Cleaned both battery terminals diligently as well as both connectors to battery. Positive side was already pretty clean, negative side was not corroded in any fashion I'm used to seeing, but had a dull sheen. System came back up like nothing ever happened.

I'll update this post with - hopefully - uneventful news in a week or two!

Now on to that bleep bleep bleepin' money pit on the river!!!

Mark

 

[wsteele]

If the battery drains again after you pull the charger off and have it all hooked up (like over night), you likely have a parasitic drain somewhere.

 

[Fless]

Update, after removing ground from battery (which tested 10.5v after that) and trickle charging all night battery shows 12.6v. Checked leads from battery to starter and to frame with both showing continuity as expected. Cleaned both battery terminals diligently as well as both connectors to battery. Positive side was already pretty clean, negative side was not corroded in any fashion I'm used to seeing, but had a dull sheen. System came back up like nothing ever happened.

I'll update this post with - hopefully - uneventful news in a week or two!

Now on to that bleep bleep bleepin' money pit on the river!!!

Mark

A continuity check is not going to tell you if that cable can conduct some serious amperage. Only verifying the voltage at the starter, under load as @Doubeleive noted, will tell you that.

 

[Doubeleive]

Yep load test or just go ahead and replace the cables, hell even my 2018 had a fried starter cable already it worked but you could see it was visibly cooked pretty good all the insulation was black and burnt off. new one looked much better and had more insulation on it. while you are at it test the alternator output, when you first start the vehicle it should be putting out a solid 13v+, maybe even 14v for the first minute or two (at the battery), after that the RVC may reduce it to 12v depending on the battery temperature.

 

[alpha_omega]

I second everything the guys mentioned above.
Plus, go buy a new battery and while you’re under the hood, check to make sure that all of the fuses and relays are in good shape and fully seated. If it’s been on and off like that, chances are it’s going to $h*+ or already has. Don’t let it take out your alternator or a set of new cables (although that would be less likely if possible without operator error).

Do you leave anything in your vehicle plugged into any of the outlets (usb, cigarette lighter front or rear)?

Have you crawled underneath and cleaned ALL of the grounds? All of them? What about the ones behind the front windshield pillars?

*Bad grounds can cause all of the issues you described, especially if there is a bad battery involved.

Have you checked the brake light switch, the cam sensor and the crank sensor.

*Brake light switch can cause the stabilitrak codes, as well as other strange problems like not wanting to shift out of park, intermittent brake light flashes, and issues with the backup camera/sensors not engaging when they should.

*Bad Cam or Crank sensors can cause a myriad of issues ranging from the vehicle not turning over like it should, driving hard, feeling like it’s missing or running hard.


Keep us posted with your updates as it may help someone else out in the future.

 

[tmeauxtay]

I had the same problems, including touching the negative lead to temporarily resolve the issue. Replaced the battery and alternator to no avail. I then changed the battery negative cable, including the battery temperature sensor that regulates charging and that fixed my problems.

 

[2011TXDenali]

Had the same issues in my 11 Denali. Radio would randomly restart while driving, various dash lights would turn on, and there would be times after turning the truck off it would have no power at all, then randomly a few minutes later would be fine.

I replaced the negative battery cable for $50 on Amazon, no issues since (*knock on wood).