voltage dropping when coming to a stop...

[jaynutz]

i just recently changed my battery and got a new alternator. took it off and had it rechecked soi that i know that the alt. is not at fault. my problem is that everytime i hit the brakes the voltage drops right above yellow and goes back up. now it doesnt do it when i am applying the brake rather when the car finally stops. what the hell can it be. i understand it dropping to 13 volts but not below. What the heck can it be, i have nothing connected to the electrical system besides my air/fuel gauge.

[F1GT]

Annoying eh? Mine has been doing that since new. So, it's pretty much "normal". You must have a stick shift. If I pop it into N while cruising at nite, the lights will dim too.
[img]graemlins/burnout.gif[/img]

[Dominic]

Yep my 2000 did that - but oddly my 2002 M5 doesn't... Maybe they changed something or it has to do with the transmission, but its normal.

[O0oSKAMo0O]

it doesnt happen on mine either it must be have been fixed for 2000

[black98V6]

yeah they proably fixed it for 2k+ but if you ask about say.. a 98.. they will say it's normal and supposed to do that.. oah and yes mine does it too..

[BillyCobin]

Mine was doing it too, except all my light would dim. I replaced the alternator and everything was fine again.

I would check the larger red wire that runs to the alternator, make sure it is in good condition. Check the ground cable, make sure it is getting good contact.

Have you replaced the belt latley? Just out of curiosity, does temprature seem to have any effect on it?

[geisencam]

I have a 1993 camaro with 85,000 miles on it and the lights don't dim when I put the brakes on hard. I don't no wwhat wrong. hard to say

[LimitedE]

A similar thing was happening to my car also. I found that condensation was building up in my tailights and semi-shorting out. Everything would dim when I touched the pedal.

[OneQuickV6]

I have it to, the rev's will drop, oil pressure, voltage, dimming lights....I have checked and rechecked the battery cables all over, everything was good, and making good connections. tested my alternator, it's good too. So I dunno.

[blackfire99]

yep same as the last guy...who knows? anyone?

[Guardsman]

I had the same problem....I changed the alternator, the problem went away for about 4 days, and then started again. A friend of mine said that he had the same problem on his truck (Chevy), and somebody else told me that GM cars and trucks have been having that problem for years.
Basically, it seems like something is eating the regulator up. Either the regulator is junk, or there is something that is causing it to go bad. I'm going to check out my wiring harness when I get a chance (it may be a while), but I'll let anybody know what I find out. LimitedE may be on to something, so I'll start there.
Basically, look for bad grounds (not reading zero ohms), or any other connections that either shouldn't show any resistance and do, or that are supposed to have resistance, but have too little or too much (i.e., supposed to be 5 ohms, but is reading 7 or 3 ohms).