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3K views 22 replies 7 participants last post by  carnut 
#1 ·
I went out to start my Eldo today and the battery was dead, its a new battery, and ive had 4 alternators in the already... I put the volt meter on the alterator and it was reading 11.4 volts.... since it has an internal regulator what else could it be???

thanks,
chaz.
 
#2 ·
Hey Chaz,
4 alternators?! Yikes. Please tell me you're NOT buying Pep Boys junk or something similar. Bargain basement components can give results like you're describing.
Do you have any kind of high-wattage electrical accessories in your car? Are you charging the battery BEFORE installing the new alternator? What kind of battery are you using?
 
#3 ·
Katshot said:
Hey Chaz,
4 alternators?! Yikes. Please tell me you're NOT buying Pep Boys junk or something similar. Bargain basement components can give results like you're describing.
Do you have any kind of high-wattage electrical accessories in your car? Are you charging the battery BEFORE installing the new alternator? What kind of battery are you using?
Well.. (Ducking) O'Rilley..

everything is stock.... no fancy shmancy stereo or anything..
I was wondering if maybe there a fluke in the CPU???

chaz.
 
#4 ·
theslider said:
Well.. (Ducking) O'Rilley..

everything is stock.... no fancy shmancy stereo or anything..
I was wondering if maybe there a fluke in the CPU???

chaz.
Duh....
no clue
check the diagonostic codes. report back and go from there
that is my 2 cents

if you don't know how to then hit the off button and the red button (to raise temp in car)
write down everything it says
 
#5 ·
JJhomer83 said:
Duh....
no clue
check the diagonostic codes. report back and go from there
that is my 2 cents

if you don't know how to then hit the off button and the red button (to raise temp in car)
write down everything it says
All i get it I039 (C) Which is suspension
and I052 (H) keep memory alive
then it sayd no ACP codes and no SIR codes
thats all. then it sits at "BCM?"

thats all i know what to do..

chaz.
 
#6 ·
theslider said:
All i get it I039 (C) Which is suspension
and I052 (H) keep memory alive
then it sayd no ACP codes and no SIR codes
thats all. then it sits at "BCM?"

thats all i know what to do..

chaz.
That tells us nothing i can't help you. Sorry man hope someone else will chyme in i am stumped on this one
 
#8 ·
Katshot said:
The "CPU" has nothing to do with this. Your issue is mechanical, not computer related.
Im lost... I take off the alternator and take it to be tested and it tests at around 13.5v, i put it on and it charges at 11.3-11.5volts. the battery is new and has been tested also and it is good. this makes no since... there has to be something im missing..
chaz.
 
#9 ·
theslider said:
Im lost... I take off the alternator and take it to be tested and it tests at around 13.5v, i put it on and it charges at 11.3-11.5volts. the battery is new and has been tested also and it is good. this makes no since... there has to be something im missing..
chaz.
One thing i just remembered, i did see a little smoke, smelled like a contact burning inside the steering wheel. but it stopped. horn and everything still works... anything in the sterring wheel era that can cause that??
thanks
chaz.
 
#10 ·
You should have the belts and pulleys checked...... The alternator sounds good, but the engine isnt turning it fast enough........
 
#12 ·
Katshot said:
What are you using to determine the charging voltage? If you're using the DIC, forget it, they are notoriously inaccurate. Also, 13.5 volts means nothing. What was the charge "amperage" at the 13.5 volts. The alt should be able to maintain approx. 13 volts @ at least 100 amps.
im not going by the DIC.. i have a voltmeter grounded to the alternator and them the other end on the change line of the alternator, and i get 11.3.. when i said 13.5. thats what the auto parts store says when they put it on there tester at the store... they say its chargin...

chaz.
 
#13 ·
theslider said:
im not going by the DIC.. i have a voltmeter grounded to the alternator and them the other end on the change line of the alternator, and i get 11.3.. when i said 13.5. thats what the auto parts store says when they put it on there tester at the store... they say its chargin...

chaz.
Could a faulty ignition switch cause the battery not to charge??

chaz.
 
#16 ·
Instrument panel control, the IPC senses when the motor is running and energizes the field in the alternator. However if the IPC is not getting power the alternator would not power up, but you would have a host of other problems.

I have a problem with my alternator, as it does not start to charge unless I rev the engine once it is running. If i leave it idle the alt will take a long time to begin to charge. Once revved it chages fine at idle. I had the same problem when it got cold out last year on my previous alternator.

Apparantly the regulator within the alternator has some built in failsafes to collapse the field if it senses an overvoltage, undervoltage or lack of rotation. I do not know what the thresholds are for this however.
 
#19 ·
theslider said:
I unplugged the alternator and got 12volts to it when i turned on the key. im at a loss....

chaz.
The alternator has a large red wire at the back, connected to a stud.
This wire must have an excellent connection to the battery. It supplies power to the field, and charges the battery. You can put an ammeter in series with this line to monitor charging.

The red wire on the 2 pin connector is just used to turn the alternator on and off. The other wire is used to provide a ground to the Generator light if there's a problem.

I suspect a corroded positive connection to the battery. There's 2 red cables going to the positive post. One is for the starter, the other is for everything else. The "everything else" cable might have 2 wires on it. The small one runs directly to the alternator.

Remove the 2 cables to the positive post. One of them has a hunk of lead inside that transfers power to the second cable in the stack. This hunk comes out. Pry it out, and clean the area inside.

Wires can also corrode inside the crimp. The only way to see this is to cut open the molded red rubber. If you cut it open, then you have to replace the cable, but at least you'll know that was the problem.

If all of that is good, then something is turned on draining the battery.
The battery is 11.5 with key off? If so, start pulling fuses until it jumps back up to 12. That will help localize it to rhe offending circuit.

Smoke from the steering column? Inside here is the turn signal switch, and horn wiring. Does everything in this area still work?
This is an important clue. If you had smoke, something is now bad whether everything "still works" or not.

Keith
 
#20 ·
keithkyll said:
The alternator has a large red wire at the back, connected to a stud.
This wire must have an excellent connection to the battery. It supplies power to the field, and charges the battery. You can put an ammeter in series with this line to monitor charging.

The red wire on the 2 pin connector is just used to turn the alternator on and off. The other wire is used to provide a ground to the Generator light if there's a problem.

I suspect a corroded positive connection to the battery. There's 2 red cables going to the positive post. One is for the starter, the other is for everything else. The "everything else" cable might have 2 wires on it. The small one runs directly to the alternator.

Remove the 2 cables to the positive post. One of them has a hunk of lead inside that transfers power to the second cable in the stack. This hunk comes out. Pry it out, and clean the area inside.

Wires can also corrode inside the crimp. The only way to see this is to cut open the molded red rubber. If you cut it open, then you have to replace the cable, but at least you'll know that was the problem.

If all of that is good, then something is turned on draining the battery.
The battery is 11.5 with key off? If so, start pulling fuses until it jumps back up to 12. That will help localize it to rhe offending circuit.

Smoke from the steering column? Inside here is the turn signal switch, and horn wiring. Does everything in this area still work?
This is an important clue. If you had smoke, something is now bad whether everything "still works" or not.

Keith
I have 11.5 volts with the car running.. i put the volt meter on the main red charge line that goes to the battery and ground it and i get around 11.5 same as if i put the volt meter on the battery with it running. everything in the steering colum works like it should... ive even ohmed out the alterntor to the battery wire and it ohms out... ill try cleaning the pos. term again...

chaz..
 
#21 ·
theslider said:
I have 11.5 volts with the car running.. i put the volt meter on the main red charge line that goes to the battery and ground it and i get around 11.5 same as if i put the volt meter on the battery with it running. everything in the steering colum works like it should... ive even ohmed out the alterntor to the battery wire and it ohms out... ill try cleaning the pos. term again...

chaz..
The true voltage of the battery is 12.6 to 12.8 volts. You must supply a voltage greater than this to charge.

Your alternator isn't turning on.
Check the red wire on the 2 pin connector. That's the 12 volts to turn on the regulator.
Check the ground to the alternator. Measure voltage from the negative of the battery to the casting of the alternator (engine running). Yes, you're checking ground to ground.

If the ground is good, then you shouldn't see any voltage (less than .25 volts or so, depending on the alternator output.). If you see voltage, check the engine ground to battery. I suspect it's good, otherwise your starter wouldn't work.

Keith
 
#23 ·
DON'T WORRY ABOUT THE SMOKE. THE HORN CONTACT HAS A LITTLE GREASE ON IT AROUND THE STEERING SHAFT. SOMETIMES THAT GREASE WILL GET HOT AND A ALITTLE SMOKE WILL COME FROM THE COLUMN. I'VE SEEN THIS ISSUE IN G.M CARS SINCE THE '80,s . USUALLY HAPPENS ONCE AND THATS IT. I HAVE NO ANSWER REGARDING THE ALTERNATOR, BUT IF THE BATTERY IS WELL CHARGED, THE ALTERNATOR WILL ONLY PUT OUT A MINIMUM VOLTAGE. TRY TESTING THE ALTERNATOR UNDER LOAD. I PERSONALLY DON'T CARE WHAT MY ALTERNATOR VOLTAGE IS, THE STRENGTH IS IN THE AMP READING UNDER LOAD. MOST ALTERNATORS ARE RATED FROM 80 TO 120 AMPS. YOU SHOULD SEE APPROX. THAT AMP READING ON A METER UNDER AN APPLIED LOAD. HAVE IT TESTED IN THE CAR AT A SHOP THAT SPECIALIZES IN AUTO ELECTRICS.
 
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