I had been driving through out the winter with my red battery light on thought nothing of it car runs good all features work....Last night me and a buddy are driving home and the car is slowly disabling features...We where talking about which battery it is...I brought up the notorious voltage regulator...Well after a taxi ride and a tow to my shop, I got some time to take a look at it..I charged the rear battery in the trunk no problem set my charger to AGM 12v and walla charged right up to full power, the secondary battery however no go dead as it gets wont take a charge. I reinstalled the main battery and replaced the secondary battery with one from Batteries Plus 14BS came with a 1 year warranty was like $80. Yes i can get one for $40 or so but I did not want to wait. Car still would not start turned over but no start I figured the crank sensor i put in 3 weeks ago was bad so i exchanged it under warranty still nothing turns over hard but no start. I checked fuel pressure because I have yet to get around to replacing my sender seal that's leaking....fuel pressure was 100% hmm started checking fuses walla again! Top Cheddar 2 15amp fuses blown in under hood box replaced fired right up!!! Bam done right no way I smelled electrical burnng and noticed smoke from the rear portion of the alternator (voltage regulator?) So long story short I ordered the regulator will replace and report back. If this was a customer car I think I would have called it the entire alternator just to be safe?

 

guess ill find out

 

I should check my voltage regulator lol.. Good luck buddy let us know what happens!

 

Since you noticed the burning smell, might be your alternator is my guess...By secondary battery, I'm assuming you mean the aux battery on the passenger side..?

Also, did you check your BCM? Good luck and report back.

 

BCM is ok I can assume for now...Going to pull the alternator friday when my voltage regulator gets here and take everything apart and asses the damages. I am hoping its just the regulator but the burning smell tells me my bearings are probably toast either way I can still rebuild it....

 

First off, who the hell drives around when the red warning light has been flashing all winter? If it is indeed your alternator, you're not only risking your own life and whomever is in the car with you, but others on the road. Burning sensation is an almost giveaway that your alternator is on its way out. Seriously, who drives for months when they have red warnings like that?

When your alternator goes, your entire electrical system shuts OFF! As in no brakes etc.

I'm assuming by your last sentence in the OP, you're a mechanic or own a car shop. I really HOPE you don't deal with customer cars the way you deal with yours.

DO NOT DRIVE THE CAR ANYWAY AND FIX IT! A dead/dying alternator is very, very dangerous on the road with these cars (for any car potentially).

 

Alternator it is, voltage regulator did not help so ive got a brand new bosch one if some one needs it...

 

Of course it is the alternator, all winter it has been trying to charge up a dead battery which is a giant resistor, when you seen smoke coming out of an alternator just what did you think was making the power, not the regulator for sure.
Just how old is the main battery?

 

main battery is NEW OEM 1 year old, secondary was original