Silverado electrical issue

**SouthernWake** · 11-11-2019, 08:42 AM

Having what appears to be an electrical issue on a 2011 Silverado

Occasionally while driving all lights on the dash come on, door locks have a spasm, and gauges drop then all reset. All happens over a second or so. Just started occurring over the past few weeks.

This has happened at both highway speeds and sitting in traffic.

Where do I start on trying to diagnose what is causing this?

**JJ1965** · 11-11-2019, 08:51 AM

I gave an 04 that does all of the same things. In addition, AC is hot, heat is Cold, and tfw Alarm goes off at random times. I have had it checked and estimates have ranged from 1500-4000 dollars. The truck has 300,000 mi on it and is worth about as much as a book of forever stamps from the USPS, so I’m going to live with it until I pay my 43.00 tax bill in January and then get something newer.

**Smilee** · 11-11-2019, 09:39 AM

Sounds like a loose ground. Probably on the firewall.

**KRT** · 11-11-2019, 09:50 AM

It’s either the fuse on firewall. Trace the red wire from positive side of battery to firewall. You will then see a fuse. That fuse gets corroded from water running down off windshield.

But my money is on alternator over charging and spiking! Replace the alternator and thank me later.

**SouthernWake** · 01-05-2020, 07:28 PM

Gonna bump this back up as I tightened up and cleaned all grounds and had not had issues until this past week.

I have noticed my gauge showing volts well below 14 occasionally while driving this past week as well. I hooked up the multimeter to the alternator but couldn't get it to replicate idling in the driveway even putting as much load on it as possible.

At this point is there anything else to test or just put a new alternator on it and hope that’s it?

**CurLee** · 01-05-2020, 07:40 PM

I would listen to KRT and replace it. Thats the problem with intermittent issues, you can only diagnose if you are there with the tools the moment it happens.

**TeamCoorsLight** · 01-05-2020, 08:06 PM

My 2011 has done this as well several times on and off. Going to try the fuse first and then the alternator.

**Bownut** · 01-05-2020, 08:09 PM

Battery cables

**DRDUCK** · 01-05-2020, 08:21 PM

Or Battery

**KRT** · 01-05-2020, 08:25 PM

Alternator

**wdhigh** · 01-05-2020, 08:27 PM

Originally Posted by KRT

Alternator

Did you consult with Tater?

**4THEGIRLS** · 01-05-2020, 08:35 PM

We were having similar issues in my wife's Suburban. Turned out it was a bad instrument cluster on the dash. In addition to similar symptoms you noted, the driver's side seat would randomly slide all the way forward, as well as the seat heaters would randomly cut on and off.

**dirtnap** · 01-05-2020, 08:49 PM

Got a 2004 Siverado with issues as well. I've replaced the instrument cluster and it's actually working now. It has some sort of electrical leak. If I don't drive it on a daily basis and let it sit a couple days, you have to jump it off. When I go out to crank it up, the screen that shows the odometer will be lit up, not with numbers but with asterisks. What you think about that KRT?

It is not my primary vehicle, but I do use it a good bit as a work truck.

**KRT** · 01-05-2020, 08:53 PM

Originally Posted by wdhigh

Did you consult with Tater?

Door locks are the dead give away.

**KRT** · 01-05-2020, 08:55 PM

Originally Posted by dirtnap

Got a 2004 Siverado with issues as well. I've replaced the instrument cluster and it's actually working now. It has some sort of electrical leak. If I don't drive it on a daily basis and let it sit a couple days, you have to jump it off. When I go out to crank it up, the screen that shows the odometer will be lit up, not with numbers but with asterisks. What you think about that KRT?

It is not my primary vehicle, but I do use it a good bit as a work truck.

Ironically we have a white 2004 dropped off Friday with same issue. I’ll let you know what we find.

**dirtnap** · 01-05-2020, 09:15 PM

Originally Posted by KRT

Ironically we have a white 2004 dropped off Friday with same issue. I’ll let you know what we find.

Thanks in advance!

**Tater** · 01-05-2020, 10:54 PM

Alternator. And considering the amount of electronics onboard and the sensitivity of said electronics a fucked up alternator will cost you way more than an alternator if you continue to ignore it.