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Battery will not charge. new battery and new alternator. The…

battery will not charge...

battery will not charge. new battery and new alternator

Mechanic's Assistant: Have you tested the battery with a voltmeter? And can you see if it's leaking or not?

The battery with the voltmeter states 12.76 while the vehicle is off

Mechanic's Assistant: What is the model of your '12 GMC?

2004 yukon denali

Mechanic's Assistant: Are you fixing your Yukon Denali yourself? What have you tried so far?

Myself at this point. changed the alternator and charged the battery

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Customer reply replied 5 months ago
Are there particular fuses I need to check? I check all the wire connections and they appear to be fine. I did notice the lights on the gear indicator became extremely low a few days ago.
Answered in 11 minutes by:
1/14/2018
Cesar Jimenez
Category: GMC
Satisfied Customers: 178
Experience: shop foreman at carmona repair
Verified

hi im cesar jimenez and i will be assisting you today. im reviewing your question now.....

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does the battery indicator light come on while engine running

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Customer reply replied 5 months ago
sir. the battery indicator light comes on and it goes off for a moment and cycles back on. the message on the dash says battery not charging

is battery properly secured and ?

are side post terminals free of debris betweem them??

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Customer reply replied 5 months ago
sir. I cleaned the terminals and resecured them tightly.

do you own a scan tool???

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Customer reply replied 5 months ago
i have a multimeter.

start vehicle and check voltage at battery?

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but do you have a scan tool??

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Customer reply replied 5 months ago
I do not have a scan tool. The power at the battery when I start it is at 12.75 and dropping. This is after I disconnected and changed the battery prior to starting.

check voltage from signal wire to the housing of the alternator while running. (gray wire C)

up

A B C D

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Customer reply replied 5 months ago
Can not find it? There are two connections to the alternator. One screws on and the other plugs in.

3 wire plug black plug behind alternator on top

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Customer reply replied 5 months ago
What do I need to do with that plug

with engine put red lead in "c" and the black lead on the housing of the alternator

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also on the big red wire there is a fusible link in the wire so also check that

Cesar Jimenez
Category: GMC
Satisfied Customers: 178
Experience: shop foreman at carmona repair
Verified
Cesar Jimenez and 87 other GMC Specialists are ready to help you
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Customer reply replied 5 months ago
From the plug, there are three wires, I tried all there and 0. From the wire that screws on I tried it and 0
Phone call session started
Customer reply replied 5 months ago
Trying to send the files.
I took a few pictures.
Customer reply replied 5 months ago
There is an issue with adding the files. For some reason it will not allow attachments.

you have to upload on at a time

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Customer reply replied 5 months ago
Photos attached. I also checked all the fuses and replaced the battery.
IMG_3763.JPGIMG_3763.JPGIMG_3764.JPGIMG_3764.JPGIMG_3765.JPGIMG_3765.JPGIMG_3766.JPGIMG_3766.JPGIMG_3767.JPGIMG_3767.JPG

okay check from the big black wire on the alternator to battery ground and check voltage

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Customer reply replied 5 months ago
Do I do this while the car is running?
Customer reply replied 5 months ago
I checked it while vehicle was on. The black wire has 11.99 going through it.
Customer reply replied 5 months ago
I checked it at the alternator connection of the wire and at the red battery jump box where the wire ends.

ok im reveiwing...

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take the alternator out and have it tested at your local autoparts

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Customer reply replied 5 months ago
But it is a brand new alternator
Customer reply replied 5 months ago
I just replaced it yesterday

did they test it for you?? ive bought many new faulty alternators before..

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Customer reply replied 5 months ago
They did not. Just getting that serpentine belt off and on is so challenging
Customer reply replied 5 months ago
Before I go through the heartache of taking out the alternator again. The battery and the cable the runs to the alternator are at 12.65/12.66. I start the vehicle and it drops to 11.99 at all points. I turn it off and let it sit and it goes back up to 12.65/12.66.

yes because its not charging.

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there is no problem in wiring from terminal to battery

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check voltage on blk plug on top of alternator

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Customer reply replied 5 months ago
How do I check this plug
Customer reply replied 5 months ago
Do I need to unplug it

start engine and connect ground lead on ground and check each wire with the red lead and tell me readings with connector connected

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also check connector for corrosion or burned pins

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Customer reply replied 5 months ago
Do I do this with it unplugged?
Customer reply replied 5 months ago
Barely.01

with the plug connected

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Customer reply replied 5 months ago
I connected the plug and touched all three wires. Zero across the board.

on the fuse box underhood there should be a big fuse sittingby itself

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yes check all the square box fuses towards the engine. if ok, then suspect alternator. go get another alternator.

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Customer reply replied 5 months ago
I agree with you my friend. I am going to pull it and get another. Give me 2 hours.

okay no problem

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Customer reply replied 5 months ago
Success my friend.
I went to the parts store and asked to exchange. When I saw the box I said it came in a blue box last night. A manager was there and said, “you paid for a new one but they gave you a referbished one”. Bot***** *****ne, I installed the new alternator and it works.

awesome glad i was helpful. thank you

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Customer reply replied 5 months ago
Extremely helpful and patient. Many thanks.
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