Electrical mayhem

[E30_fiend]

I am going crazy here.

The basics: 1990 325is 5 speed.

Problem:

While driving after te car is warm, if I tap or press the brakes hard, i.e. any braking at all, the car will have an electrical surge and the stereo shuts off and restarts. Occasionally after I have parked, if I try to lock the car from the trunk like I always do, nothing happens. If I get back in the car and try to turn the key once again nothing happens.

Here's the kicker. If I slam the door then the car will turn over just fine. Also if the trunk wont lock the car all I have to do is open the driver's door and close it once and then I am able to lock the car.

My first thought with the braking problem would possibly be the alternator not giving sufficient electricity to the vehicle and causes it to shut the stereo off. As for the whole parked car problem, I have no idea. All of this throws me for a loop.

So needless to be said, any help would be greatly appreciated.







Taylor

[jlevie]

I'd say there is a loose connection or swinging short somewhere, quite possibly near the steering column area.

[noke325]

The first problem sounds like a weak alternator. Or more specifically a weak voltage regulator. You said it happens after the car is warm - heat kills electronics - it summer. I'm assuming the alternator is not new also. Whats happening is, when you tap the brake and illuminate all those bulbs in the back, its pulling more amperage and pulling the voltage down to the point where the stereo shuts off. Let you foot off the brake - lights go out - amperage requirement comes down - available voltage goes up - stereo comes back on. Be sure to check all connections at the alt and battery. Make sure everything is grounded good too.

Second problem sound too much like a poor connection issue related to the central locking system. Maybe you have some broken wires in the drivers door jamb. Do the central locks prohibit the vehicle from cranking when active? I don't have a whole lot of experience with theses cars but have seen similar issues on others.

Happy hunting!

[E30_fiend]

The car runs fine even with the doors locked. I hadmy buddy lock all the doors from the trunk and then hand me my keys through the sunroof and everything started and ran fine.

jlevie, this is almost spot on. I replaced my steering column with a new one about amount ago. Before that the car still had the electrical issue with the radio and braking but not as frequent as now. And the whole central locking thing started after I changed the column. Is there one or a few things I can look for in particular when I pull the kneww bolster down? Its a mess under there due to stereo installers. My thought on the no start thing was possibly that the stock security system from the dealer is kicking in and not letting the car start or letting anything work.

So if someone could point me in the right electrical area, it would be greatly appreciated.

And for the record, the alternator is not new and the battery is a brand new 700 CCA battery.


thanks guys







Taylor

[jlevie]

Its a mess under there due to stereo installers

That is probably the smoking gun. You are going to have to go over all of the stereo mods carefully to make sure the right things were done and that all connections are secure.

[E30_fiend]

i think I might have figured it out. we will see once I get it warm driving home and hit the brakes. Im almost certain I figured out the no power no start situation. There was a big bundle of plastic connectors cliped together and there was one loose connection that I have encountered before. Its the black wre with a yellow stripe that controls the key switch. If that becomes unplugged then the key will turn and nothing will happen. As far as the alternator thing, I checked to make sure tha no wires were hanging from under the column down by the brake peddle so I at least know its not that. I will find out today whether the other problem is still there.







Taylor

[E30_fiend]

Ok well I just got home and both problems still exist.

I am even more livid now than I was yesterday. Can anyone shed some light on this and help me out? I am almost certain it is the alternator but how can I be 110% sure its the alternator?







Taylor

[E30_fiend]

anyone?

[416stroker]

Have your charging system load checked at autozone or whatever parts store you like. If you dont know if its not pumping out enough juice,

[IRON-E]

Have your charging system load checked at autozone or whatever parts store you like. If you dont know if its not pumping out enough juice,

Really?

[jlevie]

I think the odds that this is the alternator are slim to none. The only load that is incurred when hitting the brakes is that of the brake lights, which is negligible. Even if the alternator were dropping out under braking, the battery would carry the load.

I think it a lot more likely that the car's wiring has been screwed up in the process of installing the audio system and perhaps mess up even more during the steering column swap. My bet is that the g forces from braking is disturbing something.

[416stroker]

Really?

yes they will do it for free and you dont have to anything but drive your care there and ask them to check your alternator.

Dose the radio cut out with the high beams also?

[StereoInstaller1]

I bet a shitty install is the main cause.

Was there an alarm installed at some point, too?

BTW: 99% of all installers suck balls.

[E30_fiend]

Yes there was an aftermarket alarm system installed which was removed a while back. I didnt take the car personally to a shop to get the stereo work done. The previous owner had all that done before I bought the car.

I just need to know what wires to check so I can get this figured out. I am very mechanically inclined and can do most anything to my vehicles. I am just at a loss on where to check for these problems. What really stumps me is the fact that when I turn the key off, its like everything dies. Then I open and close the door and the OBC will light up again.


Im so over this







Taylor

[IRON-E]

I bet a shitty install is the main cause.
BTW: 99% of all installers suck balls.

^^^this should be added to your sig. And I would like to add that my shit does the same thing too.

I'm most certain that it's a fucken ground wire but paying another installer again sucks, I can live with my problem since it doesn't happen as often as yours Taylor but I have to find a solution to this problem too.