Dead Alternator?

Boone · Feb 17, 2018

So I disconnect my battery to fabricate a better hold down bracket for the Optima battery, and when I'm done, I fire the car up and go for a test ride. Shortly after I get rolling, a Check Charging System message and the idiot light for the battery comes on. I check the voltage across the battery (with the car running) when I pull back in to my garage and get 11.8V.

I checked fuse #43 (10A mini) and it's good. Is it safe to assume my alternator has died? Whatever it is, I need to remedy it quickly since I'm heading to VIR this weekend.

Anything I need to check, or confirmation of alternators dying after the battery has been disconnected would be appreciated.

Mad Hatter · Feb 17, 2018

Boone said:
So I disconnect my battery to fabricate a better hold down bracket for the Optima battery, and when I'm done, I fire the car up and go for a test ride. Shortly after I get rolling, a Check Charging System message and the idiot light for the battery comes on. I check the voltage across the battery (with the car running) when I pull back in to my garage and get 11.8V.

I checked fuse #43 (10A mini) and it's good. Is it safe to assume my alternator has died? Whatever it is, I need to remedy it quickly since I'm heading to VIR this weekend.

Anything I need to check, or confirmation of alternators dying after the battery has been disconnected would be appreciated.

You need to check the altenator voltage. If you track the car often the altenators do die sometimes. Mine would whine before they bit the dust.

Am on my third one and have a spare in the garage....

All kinds of strange things happen with low voltage..... possesed steering wheel, no power steering etc etc.

Sent from my SM-G900M using Tapatalk

Boone · Feb 18, 2018

Greeting from the worst mechanic in the US. Turns out I left the wire from the alternator to the positive post off of the battery. It slipped down near the header from its temporary resting place while the battery was disconnected, and I just missed it. Mad Hatters response made me start questioning myself.

All is well, and VIR is in my near future.

Grant 302 · Feb 18, 2018

Boone said:
Greeting from the worst mechanic in the US.

Don't be too hard on yourself!

Glad you found it. I couldn't think of anything...aside from the obvious! Always gotta check all the connections.

TMSBOSS · Feb 19, 2018

Another good rule I follow. If I work on the car and something mysteriously does not work. I am likely the cause. I Always go back and recheck everything I touched.

Wish I could say this only happened to me once.

Grant 302 · Feb 19, 2018

TMSBOSS said:
Wish I could say this only happened to me once.

Yeah, that!

Mad Hatter · Feb 21, 2018

+1... sometimes I am afraid too touch the car..... seeing as most of the problems are my fault!

Grant 302 · Feb 21, 2018

Mad Hatter said:
+1... sometimes I am afraid too touch the car..... seeing as most of the problems are my fault!

Then you're not giving yourself enough credit. All of the car's problems are all of my fault...one way or another.

Mad Hatter · Feb 21, 2018

Lol, Thanks for the correction

TMSBOSS · Feb 21, 2018

Yep. She hardly ever breaks just sitting in the garage. LOL.

Boone · Feb 23, 2018

Glad to hear the "capable" mechanics out there do stupid stuff too. On this one, I recalled that some throttle bodies go on the fritz after disconnecting the battery, and I transferred that quirk into "well, maybe the alternator goes south sometimes as well." To pass on the brutal part of the story, I actually took a picture of the battery and tray before I did the work, did the work and reconnected the battery, whined about the alternator failure, then realized I took a picture, looked at the photo and saw the missing wire connector. I traced the alternator wire and determined the headers had no need for 13.5V power.

What a Maroon!

TMSBOSS · Feb 24, 2018

Moron??? You fixed it. Ever wonder why you are not allowed in most service areas?

Boone · Feb 27, 2018

"Maroon" was intentional. I grew up on Bugs Bunny.

I "fixed it" is generous. I just corrected my screw up.

Grant 302 · Feb 27, 2018

Boone said:
"Maroon" was intentional. I grew up on Bugs Bunny.

I "fixed it" is generous. I just corrected my screw up.

I think he got it! ...I certainly did, and appreciated the Bugs Bunny reference.

I took TMS' comment as many of the real morons work in some service areas...and *that's* why we're normally not allowed back there.

Boone · Feb 27, 2018

Damn! I am a Maroon!! Thanks for spelling it out for me. Been a long day with nine hours of driving to look at a crane system in GA that has seen better days.

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Dead Alternator?

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Boone

Professional Thread Killer

Mad Hatter

Gotta go Faster

Boone

Professional Thread Killer

Grant 302

basic and well known psychic

TMSBOSS

Spending my pension on car parts and track fees.

Grant 302

basic and well known psychic

Mad Hatter

Gotta go Faster

Grant 302

basic and well known psychic

Mad Hatter

Gotta go Faster

TMSBOSS

Spending my pension on car parts and track fees.

Boone

Professional Thread Killer

TMSBOSS

Spending my pension on car parts and track fees.

Boone

Professional Thread Killer

Grant 302

basic and well known psychic

Boone

Professional Thread Killer

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