Gauges flicker and lights dim with window usage

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

4Eyedturd

Member
Joined
Jul 21, 2025
Posts
48
Reaction score
45
It appears as tho my 05 Yukon has developed some type of electrical issue. At idle I’ve noticed the dash lights will slightly flicker, also noticed when I roll the windows up or down it’ll cause the headlights and instrument lights to dim. I’ve watched the voltages with a scanner and the idle voltage will vary from 12v up to 14v within a matter of minutes. I’m not sure if that’s normal operation since it has the sensor on the battery cable or if the alternator is on its way out. I want to throw a new battery and alternator on it but don’t want to just throw parts at it.
 

Fless

Staff member
Moderator
Joined
Apr 2, 2017
Posts
16,612
Reaction score
34,385
Location
People's Republic of Colorado
normally that is a indicator of a battery getting weaker, how old is it>?

^^^ This, as well as bad battery cables and/or connections and grounds.

EDIT: do a voltage drop test to evaluate the big cables and connections. Doesn't cost anything but time.

 
Last edited:
OP
OP
4

4Eyedturd

Member
Joined
Jul 21, 2025
Posts
48
Reaction score
45
^^^ This, as well as bad battery cables and/or connections and grounds.

EDIT: do a voltage drop test to evaluate the big cables and connections. Doesn't cost anything but time.

Is there a cheaper/non snap on brand of that tool to log voltage? Seems like it would be handy in these kinds situations
 

Fless

Staff member
Moderator
Joined
Apr 2, 2017
Posts
16,612
Reaction score
34,385
Location
People's Republic of Colorado
Usually just a digital voltmeter would work. If you want a graph, you could try an inexpensive handheld scope, but it's not necessary for the measurement. He uses the graph for clarity for the viewers.
 

LsHart

Senior Member
Supporting Member
Joined
Dec 31, 2025
Posts
686
Reaction score
651
Sounds like when u have a system in ur ride and when it hits hard, stuff dims. As stated above, week batt or alternator is weak or a cheap aftermarket.
 

S33k3r

Elite Member
Supporting Member
Joined
Aug 14, 2017
Posts
2,893
Reaction score
4,189
Location
Dallas, Texas
We don't have enough information to point at just one thing -- everything will be a guess. But it could be your window motor dying -- is it original? It could also be the window track binding. I'd suggest cleaning that even if it is not the problem. It will well your motor out more quickly if you don't. And you can "grease it" with a silicone spray. I think they sell it for RVs... I just don't have my can handy to check the name.

The actually symptom is that you are not generating enough power to move the window up and run everything else. So you either have a power problem, a window motor problem, a window track problem, or some combination thereof.
 

LsHart

Senior Member
Supporting Member
Joined
Dec 31, 2025
Posts
686
Reaction score
651
I was giving a demo to the folks that have had a system. When a electric motor like a window motor, it'll draw power witch depending on the age of the said motor, it will amp up when getting old so to speak. On top of that. If the relay has been in that spot since factory. I would say the relay is worn-out. Contactor worn. So to combat the issue, replace relays after window reg assemblies have been replaced. The parts in the fuse boxes do have a life.
 

mikez71

Full Access Member
Joined
Mar 9, 2023
Posts
3,334
Reaction score
4,137
I do like my amazon 'a-premium' brand window regulator. It goes up as easy as it goes down.
The original on the other side goes down fine, but is pretty slow going up.. For ~$55 I plan to do the other side before long..
 

LsHart

Senior Member
Supporting Member
Joined
Dec 31, 2025
Posts
686
Reaction score
651
Pay up. Been there did that. Already failed and on to another website. The last one I replaced just started to as it hits all the way down, the window will tilt to the rear. 8 months old maybe.
 

mikez71

Full Access Member
Joined
Mar 9, 2023
Posts
3,334
Reaction score
4,137
Pay up. Been there did that. Already failed and on to another website. The last one I replaced just started to as it hits all the way down, the window will tilt to the rear. 8 months old maybe.
You talking about the amazon window regulators? If so, what's the better option?
 

LsHart

Senior Member
Supporting Member
Joined
Dec 31, 2025
Posts
686
Reaction score
651
Hell not sure. Closes to oem I guess. I haven't found anything that doesn't lean or rattle. With in a budget.
 

LsHart

Senior Member
Supporting Member
Joined
Dec 31, 2025
Posts
686
Reaction score
651
One rear is a Amazon buy. The other rear is a parts geek buy. Not sure where one is vs the other.
 

mikez71

Full Access Member
Joined
Mar 9, 2023
Posts
3,334
Reaction score
4,137
But was it the 'A-premium' brand? :p
Just kidding, all the amazon ones look like the same unit..
And my 'A-premum' door handles on my GMT900 have fading black plastic already..

But otherwise all working fine.. so far..
 

LsHart

Senior Member
Supporting Member
Joined
Dec 31, 2025
Posts
686
Reaction score
651
I do have A-premium catts on my malibu! 2 years strong so far.
 

Forum statistics

Threads
138,035
Posts
1,997,528
Members
102,973
Latest member
CRN_25
Back
Top