**UPDATED** Under Voltage, Consumer Defective, alternator, help
i replaced my battery a couple of months ago. so its pretty new. two nights ago, after about a 50 minute drive, i pull into a parking spot and up comes
"Under Voltage Consumer Defective"
crap. ok. i come back an hour or so later, it turns over. ok good. i monitor the voltage. seems to be in the high 12s range: 12.6-12.9 for most of the drive back.
yesterday, voltage was in the mid to low 13s: 13.0 - 13.5 for most of the time.
today, voltage is everywhere: i've seen 13.5, 12.5 and 11.9........started off higher and as i drove, dropped into high 12s, then lower 12s. it is starting to hesitate to turn over on startup
so i'm wondering, is this an alternator issue?
i have NOT gotten that error message again
like i said, basically a brand new battery
i monitor battery voltage (my readings) through OBDII
i have updated seat modules
also, if it IS an alternator issue, which one do you guys recommend/is the right one? i dont want to deal with incorrect pulley issues and such (8 rib vs 6 rib)
i searched and found some links:
http://www.bimmerspecialist.com/part...54-02-02%2088#
http://catalog.worldpac.com/ibusines...art=Alternator
also see post 18: https://mbworld.org/forums/c32-amg-c...ternators.html
thanks for your help guys.....
and i got the under voltage consumer defective error message again.
today it was fine and in the 13s all day and (and 12.9s). i ordered the alternator anyway. is this normal behavior as it goes out? one day it might be perfectly fine and the next day it is everywhere?
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The only variable I can bring my down to is a wet engine bay causing a short circuit.
We have been very dry lately here until the last couple of days we have had massive down pours of rain and i park my car on a hill (facing down). I have removed the weather striping from the car so the engine area gets wet.. even though there is the spill tray for the battery cover I'm still unsure..
The weird thing is the error message today didn't come on today, it came on this afternoon on the drive home.. but once again iti was raining heavily all day.
Maybe my alternator is going but I'm also sceptical and think it could be something else.. just wish i could monitor battery voltage.
you can monitor battery voltage through the "super secret menu" accessed through using your A/C buttons.
i monitor it through my OBDII gauge though.
and it hasnt been raining here, so i'm not sure that is what it could be. i have been told that the alternator usually goes about between 80-90 and i'm just about to hit 90k. so.... pff...i just hope that it is what it is....or else i just bought an alternator for nothing.
Yeah well I'm on 106k so it probably sounds right too for mine.
Does yours come on every time you drive and random intervals or is it a set sequence that you know it's going to come on (ie/ 2mins after car starts or something)
Both times for me it has come on in heavy traffic with the engine idling (and it sounded like it was idling too low too just before it came on).. so the alternator theory works with what happened to me.
voltage started high again and over the course of the day, has dropped to consistent low 12s and high 11s.
BUT, i did notice my coolant temps and air temps were at least 10 degrees warmer than usual today....on a 66 degree day.
how does this logic sound? alternator on the way out, so more voltage being drained from the battery BUT to help prevent that and work with the less voltage, the fan is affected....either comes on later or spins slower, and thus uses less energy? thoughts?
either way, alternator comes in tomorrow and i'll be doing the install likely on saturday
I would just replace the alternator and see what happens. Since your problem is essentially power generation.
I would just replace the alternator and see what happens. Since your problem is essentially power generation.
i just got my alternator. i'll install it tomorrow and report back to see if my problems are solved.
voltage today started at mid 13s. stayed there for 15 minutes. dropped to mid-high 12s for 30. and then low 12s for another 25 minutes. and then dropped down to 11.7-12.3 range for a minute.
anyone know the avg/correct running voltage during driving?
alternator, what I was trying to point out is sometimes it's not what we
think at first. That said, any starter solenoid is attached to the starter
since it's the solenoid that engages the starter to the flywheel so it can
turn the engine over. On my sons car I just followed every cable from the
ground at the battery to the positive cable to all cables on the alternator.
Checking stuff is free and sometimes you stumble onto what's wrong.
Sometimes it's just a failed part. Before I bought a new alternator though,
I would take mine off and have it tested for free at any auto parts store.
No return policy on most electrical parts and if yours checks out, you just
saved $400.


