alternator gauge drops when brake pedal applied

[RichMason]

Greetings Pelicans. So my problems with the faulty readings on my temp gauge were resolved with a change in instrument clusters. However, now my alternator gauge reads higher than before (over 14 when the car is cold and between 12 and 14 when warm). The problem I am complaining of is that the gauge dips significantly when I depress the brake pedal, about 1/8-1/4 of an inch. Any suggestions as to what might cause this? Also, the new instrument cluster is out of an 86 Turbo and I have an 87.

[TheCooler]

Yeah, happens to me too when i stomp on my pedal, nothing to worry about. Its the ABS I believe. Might be a battery going bad? Check it out.

[SoCal Driver]

Take out those 100 watt bulbs in the brakelights.

[RichMason]

Stock bulbs and no abs on my car...I need to pull out my voltmeter and check the battery and alternator.

[1.2gees]

It's probably the ground for the tail (brake) lights. Check/clean under carpet.
Ahmet

[Zero10]

Hmm, well your voltmeter readings sound normal to me, that's where mine are.
However the drop is definately not normal. Mine will dip a little, just for a second until everything adjusts to the load (or the bulbs warm up and draw less current, who cares which one =). I wonder if the brake lights and instrument clusters share a ground or something?
It almost sounds like the voltmeter is seeing the voltage drop on the wire for the taillights.
Stupid guess, but it's an idea?

[SoCal Driver]

Originally posted by RichMason
Stock bulbs and no abs on my car...I need to pull out my voltmeter and check the battery and alternator.

Really?

I had to take mine out because of the voltage drop.

Well that and the ticket I got from the cop I blinded.

[Zero10]

Lol, what on earth would you need tail lights that bright for?
My rule is when the tail lights are brighter than the headlights, then it's time to take them down a little =P

[SoCal Driver]

Actually I had 50 watt halogens in the back up lights. Started to melt the tail light reflectors.

The euro fog tail lights are connected to the brake lights though.

[Zero10]

fog tail lights?...
Which ones are those?

[SoCal Driver]

Originally posted by Zero10
fog tail lights?...
Which ones are those?

The ones on each side of the license plate area.

When you pull the cover on the bulb holder you will see that there are no sockets in them. In Germany they only use the outer one. Guess in England they use the inner one. But then it would be the outer one there. Even a spare wire for it.

IceShark had been getting extra sockets for sale. You can find them at the VW dealers. Uses a single element. Although a double element does have possibilities!

Edit: The euro rear fog lights are the ones just inside of the regular running lights. The brake lights are the double window ones next to the license plate recess.

[IceShark]

Hugh, I think I cleaned out the entire distribution inventory in North America for good and sold out all the sockets to Porsche owners. The sockets are discontinued for good as far as I know. So you need to go to the parts breakers for Porsche or VW Type 1 bug to get used ones if you want to light up the dead cells. Or I guess solder some wires on a bulb and tape it in the lens hole. The same socket is used on some Audi cars as well.

The euro fog lights are the two inner upper and lower cells in the taillights. These are actually a single connected cell and are the ones used in North America as the brake lights. Sort of goofy but that is the way they were assigned.

[Manute]

My car has only one fog light,at the left,between the brake light and the turn signal.

[SoCal Driver]

Originally posted by Manute
My car has only one fog light,at the left,between the brake light and the turn signal.

Right below the back up light!

That light has an empty socket here in the states.

[vital-transform]

I have a few sockets PM me...LEDs are a great alternative!

[Zero10]

Hmm, I am interested in lighting up the empty cell.
Does anybody still have sockets for sale (or free for a poor canadian boy?)?