[dmax]

Background: One day in December 2008 after warming up my car I pulled out my driveway and immediately my cars dashboard gave me SES, AIRBAG, BRAKE, CONVERTIBLE TOP MAL, ABS, and a whole Christmas tree of lights i dont remember all of them. But anyways turned off my car to see if that would solve the problem and when trying to start it up again, it just cranked but wouldnt start. So then i got the battery change by Tischer BMW in Feb 2009, everything seemed to be going well after that, i drove it normally, no problems. Then in Dec 2009 same sh*t happened again where my car gave me those sh*t dashboard lights. I then turned off the car and after an hour, it started back it fine. I thought everything was solved but then after trying to drive it 100 feet, the lights come back.

Currently: I charged the battery at Autozone, they said it was a good battery when they tested it. Then i tested it myself and it gives me a reading of 12.33 volts. When i start the car and turn on the Xenon headlights and heater to 91 degrees full blast, the voltage reads 13.8 to 13.86 volts. So is my alternator bad... what else could it be if the problem is not the alternator????????

PLEASE HELP!!!!!!!

Jone or Perry or both,

Mileage? Year? Sorry if I missed that.

Aftermarket things?

What other elect. work might have been done incidental to original problems?

I like the cleaning and replacing brushs, regulator, but haven't done this myself. Had alt out...should've stepped up my diying! Anyone with link or 'crib' notes on this...Mr. Juan? Alt in, think you said for both brushes and reg, right?

Anyway, OP...Don't forget the basics too that many skim over too quickly in diagnosing elect. issues...

Battery cables tight? With replacement bats. sometimes terminals are too small and if you or mech only tighten nuts on connector, cable might still be loose...generally, I think that'd show up pretty soon and as intermittant odd gremlin sorts of things.

Parasitic drains from Aftermarket stuff that you don't think have anything to do with other elec. issues...really do. I've read often of diying this or that...or mech that gets things to work, but is pulling power incorrectly...often so it's drawing power continuously behind the scenes.

Shorts somewhere...loose fuses...get to know your ground locations...might be loose somewhere.

Ah, my favorite...

totally 'unrelated' failure/repair of another system--cooling, lubrication, CCV, PS, elbow...causing fluids to get into connectors and foul up signals to car.

OP, sorry for this, but is your car driving? Just lights and no other symptoms in engine or switches, etc?

Have you scanned for codes for free at Autozone? I haven't ever, but heard that's a service they do...bring codes back.

But first, look into basic things and report on other repairs.

I like a puzzle and would be glad to play! (Away all day though!)

HTH...sorry if you're already past all these suggestions!

Doug

 

[dmax]

littlegti is correct. When you had your alternator tested, you only had it tested for voltage output. To get the full picture, you also have to know what the maximum amperage output is. You can have great voltage, but really sh*tty amp output, which could possibly ruin an otherwise good battery. Low amps would also have your car celebrating "Christmas" with all those lights. Get to a good indy to have a full charging system evaluation, or if you have the equipment, the voltage output of the alt s/b approx 13.2 to 13.8 volts. Amperage output can vary according to your cars equipment package, however it should sit at the 115 to 145 amp range with the idle at 2k rpm & all equipment off. HTH. Chas

So, sounds like alt issue that also hurt battery maybe?

You did try to pull the cables off, right? Just checking...I'm OCD!

Chas seems to know what he's talking about...as did Littlegti...I'd buy it!

New bats do go bad, btw, just randomly, so could be that too...but seems odds favor some reason for that.

 

[dmax]

Jone,

The alternator has a large cable coming into it, bolted beneath the rubber boot back there, but it also has a connection...so a connection spot on the alt and a wire nearby undoubtedly want to join! If you can, spray plastic safe electrical cleaner in both spots and wait for it to dry.

I haven't done work on alt other than to remove it...but would guess that's a connection to the voltage regulator and is certainly needed for something...my guess is voltage regulation, but I don't know what that means specifically!

Also, nothing personal, but I don't think I'd go back to a garage that might've been doing some work on the car...they either forgot, or remembered to forget...or just randomly pulled on it...connectors on our cars seem to stay together quite well.... If it's a friend or yourself...bygones!

Doug

 

[dmax]

yeah i really wanna put the wire on the connection but im just scared cuz i dont know what it is, if anyone knows, can you share some thought on it? i mean Doug if u say the connections are really stable, that means this connection thing must have been off for a year at least because the last time i took it to the dealer was more than a year ago, so im just currious as to what this connector is?

Search realoem.com if you haven't already. Also, search voltage regulators...I know they go bad and show up as odd electrical gremlins in car...and although I do believe the connections are stable and better well should be, I'm thinking that maybe you can live without a voltage regulator. The cable carries power to battery, so the connection has to do something, and I know the alt has a connector...just was there a couple of weeks ago. So, me, I'd disconnect battery just to be safe; plug it in after cleaning it out well and letting cleaner dry...blow out with compressed air? Recon after waiting as long as you can stand to wait...recon battery. Pray that this Doug guy isn't an idiot...which I'm assured by many that I am!

If there's a connector hanging free, and it fits into the alt that has an empty connector, you know that's the one. Every connector it seems has a slightly different config...not all of course, but if it plugs in and there isn't any slack in the line, they were meant to be together.

Anyway, since there's only the alternator and a connector, and I know the alt has a replaceable voltage regulator, I'm pretty sure that's what the connector is for.

Might it have failed...you'll see when you plug it in whether it's firm or not...might've had someone nick it in prior repairs somehow...might never have known.

Doug

 

[dmax]

Sorry, backup a little. I'd assumed the extra wire was one with a connector at the end, but now I'm wondering if you mean just a single wire hanging around?

If this is a small wire and there's an empty hole in the connector already plugged into the back of the alt...then get new connector and hook new wires into it...think that'd be best...you can't really just stick a wire into a connector hoping it'll stick...it'd be very squirrley!

If the wire is 1/4" thick or so hanging loose, that's the cable to battery...and it should be bolted under the rectangular black rubber cover on back of alt.

Sorry if this confuses you...does me too!

Doug