How should i go about this problem
 

Alright, heres a little problem, When i turn on the parking lights or headlights the lights to my stereo dim alot, and when i get on the brakes, the lights in the gauges dim a little too.


I just replaced the battery with a new one.

I think its the alternator so i bought a used one.

But i havent installed the alternator yet so i dont know for sure if thats it, what else is there that i can look at? Or what should i might as well upgrade if im gonna be replaceing a bunch of parts on my car anyways? maybe HyperGround wires?

have you checked to make sure that your interior switch is turned all the way up...

possibly bad battery cable or poor connection with the new battery?

next, test the alternator for voltage. with the car running, take a voltmeter to the battery cable. it should be something like 13-14 volts. if it's low, your alternator should be replaced.

Also could be bad grounding...

sounds like the alt. just in case check the grounds, clean and tighten bat cables. If that doesn't help then turn on every accessory including the wipers and check for low voltage. Good luck :)

I have the same problem...just got a new alternator but no luck at all...Ive had this problem ever since I bought the car 3 years ago!

Going to do the battery relocation this next week and change all my grounds...I'll let you guys know if that'll fix the dim...

By the way...mine is a split second thing... every time I hit the brake everything from the headlights to interior ligts dims/flicks

:withstupi

Did you check for voltage drop for the alt to the battery. Measure the voltage at the alt terminal and at the pos terminal of the battery, if there is a noticeable drop try running another wire from the alt directly to the postive terminal. Leave the original wire in there.

ooo, ok any suggestions on where to get cheap ground wires?

What's so stupid about that?

Most stereos are designed to dim when you turn your lights on. There is a wire (usually yellow i think) that goes into your stereo harness (usually something called illumination) that will change the brightness of the deck according to the lights. When you turn your lights on the stereo manufacturers make the assumption that it is dark out. Therefore they dim their equipment so it wont be harshly bright compared to your other illuminated equipment.

Now you are correct when you say you have a problem when you hit the brakes it dims the lights...those are supposed to be unrelated. Sounds like a short to me or a loose wire.

Shawn

Nothing stupid about it, I just like that smiley :) It was the obvious answer, but thats exactly what I would have suggested too.

You can buy the from rx7store.net for like $150 I think. Damian did an excellent write-up of his ground wire system, do a search for ground wires and his name, you should find it.

You can actually make your own with SS braided straps, and some nice copper connectors. But thats more work.

So, PhatManBUD, did any of these things help you out?

I have been having the same problem, too. Interior switch all the way up and when I hit the brakes, the headlights dim until I let off the brakes....

You guys should do a search, I know I've seen a few posts about this. The solution is bound to be there.

Good Luck

I was actually interested in hearing about his personal experience.

You can also go to a stereo shop and buy the wire there. Get atleast 10 gauge wire and some ring terminals. I've done that with all my cars. 10 feet of wire and ring terminals came out to $20 dollars which is way better than paying $150 for the same thing in a fancy box. Check the archives for Damians post on grounding. It gives you a good idea where to put your ground wires.

I bought 15 feet of 6 guage and 16 terminals for 20 bucks. Grounded everything in site.

yes my does the same hitting the brakes dims everything, does anyone know the normal voltage, my power fc reads around 11.8-13.0 when the car is on depending on what is on.