So since I've owned my truck, my lights have always flickered when turned on (every light including guage lights). They didn't flicker on and off. They just dimmed and brightened in approximately one second intervals. It never really bothered me before but I decided to replace the external voltage regulator tonight. The new VR stopped the flickering. However it revealed 3 things:

(1) My alternator was going bad.
(2) My guage lights, now not flickering as before, were alot less brighter...almost to the point of not being readable at night.
(3) My battery, installed new last January, is low on charge already.

Ok. So I know I'm going to have to buy and throw a new alternator in. My questions are:

Why would my guage lights be brighter while flickering than they would be while remaining at a constant brightness with the new regulator?

Also, will replacing my alternator fix my problem with the dim guages?

Sorry for the book. Can anyone help?
Thanks in advance

Chris

 

Voltage regulator? I thought the PCM did that.

What is the voltage at the battery now when the engine is running?

Was the volt meter osscilating when the lights were flickering?

The reason I ask is sometimes there is more than one problem such as the possibility that the headlight switch and the altenator.

 

I put a new regulator on it last night and it fixed the flickering problem. The volt meter was oscilating when the lights were flickering, as well as the guage that measures battery charge in the truck. The battery was drawing pretty heavily on the charger when I plugged it up last night. I think the battery was overcharging. I don't even listen to the radio so the only real draw on the battery is my lights and starting the truck.

 

i have the same problem. I put a new alt on it. didnt help, the new VR stopped the pulsing BUT made the battery charge at 15v which is a little high. I put my old VR back on and it pulses between 14.2-15.3v. I have no idea what the problem is. oh also a brand new battery. Super Start 12v 800CCA

Oddly enough, it did it really bad until i put my new headlights in, then it wasnt as noticeable but still is