so it's been doing it for a long while. can't remember if it did when i first bought the truck which was about 8 months ago. moving, stopped, doesn't matter. when i roll the windows up or down the head lights and dash lights dim. no electrical, audio or other upgrades so far so i can't blame it on that. went to advanced auto and they tested the battery and alternator with a hand held and said both were good. searched and as i suspected most of the issues with dimming lights have come out of audio upgrades. any ideas as to what could be causing this?

 

mine does it too

 

FINALLY! my truck is normal lol. bugs me to no end. use to the dimming lights with big stereos, but not stock.

 

Mine have done this too since my truck was new, even before I put my amp in. Although with my HID’s the headlights don’t dim anymore, but the dash still does.

 

put a 1 farad capacitor in your truck and it shouldn't dim any more

mine did it before i put the stereo system in, now it doesn't
but i do have led dash so i don't know if that makes a difference

 

Mine has done it since I can remember also.

 

My Ford Escape did this from day one and, as of last month when I sold it, still did it. Any big draw like a window motor would have some effect on the brightness of the headlights.

My window cranks on the Ram have no effect on the headlights, since they are manual.

 

A 1farad capacitor between the battery and main cables would probably not be big enough, and to do it just for the windows would be alotta work

I figured you were talking about stereo, Marx, but he said he didnt have anything special

 

the capacitor is wired in parallel so it really easy + to + -to-,
the reason the lights dim is because the window motors draw amps away from other accessory's, because the electrical system can't keep up with everything. By adding a capacitor you are allowing more storage capacity in the electrical system and the windows will pull power from the cap and not your lights

1 farad cap should be large enough, I've got a 1.5 farad in my truck and even with huge bass i don't get dimming, because the op doesn't have anything special for a stereo system the cap will act as a reserve, to reduce the sudden electrical draws of accessory's coming on, and should reduce dimming

 

well your truck already has a capacitor, what im wondering if it would be alright to wire the capacitor strait from the main battery + and - or if you could only run accessories which would be alot more time intensive

You have a capacitor on the lines going to your amps right? He doesnt have that so he would have to put ANOTHER inline. Yours is geared towards the stereo im sure, his is just the normal lights/comp/etc...I wonder what the stock capacitor is rated at?