So tonight I was driving the FJ 60 home from a friends and noticed that the headlights pulse between regular and a little bit brighter on a pretty steady rhythm. Not high beam bright just enough to be noticeable. I turned off the radio and heater and this didn't seem to make a difference. Then it would stop for a couple of miles and start again. The other thing I noticed was that the dash lights were doing the same thing and the elctrical gauge would jump from 14 where it normaly rides up to 16 or pegged out. For those of you who aren't familiar with the FJ 60 the amp gauge is from 8-16 in increments of 2s. So obviously there is some sort of intermittent power surge but what is causing it? I have no idea. My best guess is that the alternator is about to give up the ghost anyone have any thoughts before I start playing replace the parts? Thanks for your time. :D

Maybe check you batt ground and pos terminals and cables. I usually do the ole baking soda/ water trick when I get some corrosion.

Typically the voltage regulator will cause power surges when it is going out...or it will just drop one of it's three fields all together.

I would try trouble shooting this first...Also, I don't know if an LC is internal or Exteral...

It could also be your ground though...Screw it, sell the thing and buy a SCOUT:D

Volt meter or ampmeter ??
varying voltage would be a bad voltage regulator
varying amp(load) could be a bad ground/failing component.
like already stated check all your grounds/wires , also make sure you've got a good connection between the frame and motor and batt

So I checked and it has a new alternator with an internal voltage regulator so that probably isn't the problem. I checked the battery and it is registering 13.07 volts so how do you check for a good ground? Could it possibly be a faulty headlight switch?

To check ground potential, use the mV display on the meter and put the red wire to the chasis and the black to (-) battery terminal, also probe to the engine. To answer your other question about the switch, yes is could be that as well or the dimmer module(portion) but usually a pulsing is a bad ground, does the light intesity increase with engine rev's? Also check the terminal conditions as this is usually problem on the light and battery, clean if dirty. Another possibility is a loose connection on the alt, fuse panel...happy hunting

Okay I didn't have a mV setting on my meter but I do have continuity on the ground wire. The new thing it is doing is running at 12 voltsa and then as I accelerate the headlamps get brighter. So I am going to replace the ground cable tomorrow and see if that does it. Both of the cables look pretty old and they have those old clamp connectors that always cause the cable wires to fan out like an old broom.