2002 Blazer lights flicker.

We just pulled it off the lot yesterday and are first night driving this thing I notice the lights have a light flicker to them. Not just the head lamps but all the lights.

I checked some other forums. So far I see it can be eather a faulty ground connection or a bad voltage regulator.

Is this something I should worry about?

I also plan on installing a hude stereo system from my old car into this thing so I plan on running a hyper grounding system under the hood. Should I give this a try first before rushing it back to the dealer?

Appreaciate the help!

The headlights are doing this?

Is it that notceable?

Head lamps and interior. Not that noticable like they shut of, but they flicker.

I just opened an alldata account and it seems like it could either be a bad ground, or voltage regulator in the alternator.

yea, I would be stating at the ground first and work from there.

Make sure all the grounds are tight and clean with no corrosion on the connector and the surface.

Funny thing is my dads denali is doing this every so often. IS it a loose ground?

yea, it could be. That is why you always check them first.

From there I would think it is an alternator.

Remember guys, always charge you battery up to full every year.

Well it only happens when you let off the accelerator and it happens every so often. I'm confused.

I think its fixed. I moved my Drycell Car audio battery (optima) to the blazer.

I added a hyperground system. I used 4AWG wire. Three extra ground points (one straight to chasis which I noticed this truck doesnt have, one to the motor, and one at the alt).

And one straight run from the alt to the positive terminal.
I got a nice voltage jump aswell. All I need to do is check it at night now.


As far as your father denali, is it a flicker or are they dimming when you let off the gas? If its a dimming problem it could be the alt or the battery is on its way out.

I would check the voltages with the vehicle on and off.
On should be at 14+ volts and off should be at 12v.

I think it makes a 2 or 4 point drop in voltage when it does it.

on my 96 blazer it was doing the same thing... i checked the alternator it was fine i add grounds didnt work.. then i didnt a light check and i found out that theres a black box by or under the code reader plug in.. its the keyless entry .. i disconnected it and it works fine no flicker... i never had a fab for the key less entry so it doesnt bother me

um never mind about the black box when i took that out for a while then put it back in it was fine that was in sept i think but now its jan now its doing it again