weird battery issues

lochenjons · #1 (**permalink**) 03-07-07, 12:06 AM

hey guys i have a problem with my caddy. the no charge light comes on really dimly when i turn my brights on or when i turn the a/c or defrost on. also the light comes on really dimly when im rolling down my windows. if i roll my window all the way up and keep pressing down on the switch to roll it up, the light comes on pretty brightly. is this because i went to too many drive in movies? have the twilight sentinel enabled? does that really drain a lot of battery?

Cadillac Giovanni · #2 (**permalink**) 03-07-07, 12:21 AM

I'm not sure. A "No Charge" usually indicates that the alternator itself is not delivering a charge to the battery, or simply that the battery is holding a charge poorly. Have you had trouble starting the car? That uses more battery power than anything.

I know I killed mine repeatedly by listening to the radio with the car parked. I had to have the key in the on position because the accessory position in my car doesn't work. After enough of this, the battery will lose it's ability to hold a charge well. You may want to invest in a brand spanking new one if you get the chance.

I'm not sure about the twilight sentinel either, i've never used mine...

If the car is starting okay, then the battery is holding a charge fine, but if the alternator is struggling to deliver a charge to the battery during operation, it may be getting close to time for a new one...

lochenjons · #3 (**permalink**) 03-07-07, 12:33 PM

no the car is starting fine... havn't had a problem with it yet. the battery is pretty new i got it when i got the car last august. maybe i should charge it

Pckstude · #4 (**permalink**) 03-07-07, 01:33 PM

Quote:

Originally Posted by lochenjons

no the car is starting fine... havn't had a problem with it yet. the battery is pretty new i got it when i got the car last august. maybe i should charge it

Sounds like the alternator needs to be checked out. It's either not putting out enough amps, or volts. Either one will not be able to keep ur battery charged up the way it should and eventually u will find that u won't be able to start ur car cuz the batter is dead.
When getting ur alternator checked out, make sure the battery cables are in good shape and that the connection is clean where it comes in contact with the battery itself. If the cables are in good shape, and the connections clean, then u may have a problem with a ground.
Checking for a ground would call for inspecting the ground end of the negative battery cable. It could be dirty or loose. Next one would want to inspect the body to engine ground for a good connection. There is also a voltage drop check that ur mechanic can do with a voltmeter.
New batteries can go bad too, like anything else. More than likely tho, it sounds like ur alternator. Keep us posted. Remember, look for the simple things first.

Old Fleetwood · #5 (**permalink**) 03-07-07, 05:23 PM

Are the belts properly tight?

The Ape Man · #6 (**permalink**) 03-07-07, 09:11 PM

You probably have 1 or more bad diodes in the alternator. It will make rated voltage but won't be able to deliver rated current in that condition. Everything will seem OK until you start turning on things which draw heavy current. A rainy day with the defrogger, wipers and blower will show the thing up. Another hint is a whining on the stereo that changes with engine speed. If the stereo was clean before and now has some alternator whine then listen to it. Alternators whine when they need help.
They sing when they work properly.

Red_October_7000 · #7 (**permalink**) 03-08-07, 01:37 AM

Quote:

Originally Posted by Pckstude

It's either not putting out enough amps, or volts. Either one will not be able to keep ur battery charged up the way it should and eventually u will find that u won't be able to start ur car cuz the batter is dead.

Quote:

Originally Posted by The Ape Man

A rainy day with the defrogger, wipers and blower will show the thing up.

This thread is a festival of typographical errors. At any rate this does sound like an alternator problem. It's probably not doing much; I've had cars with good batteries have the alternator die completely and the "Charge" light come on only when you use something electrical.

Edit: Oh yeah -it could be the regulator, too. I don't know where that is on that car though, on some cars it's integral to the alternator.

Old Fleetwood · #8 (**permalink**) 03-08-07, 02:54 PM

Hey, Red -
Those aren't Typos!

The BATTER was missing and that was really a problem, because
the
DEFROGGER didn't work and the whole damn car was getting full of croakers!

lochenjons · #9 (**permalink**) 03-08-07, 09:13 PM

so im guessing its the alternator... ill take it down to autozone and have them test it. how much do new ones cost? like what $100 or something?

Old Fleetwood · #10 (**permalink**) 03-08-07, 10:56 PM

Hokay - - -
Down at your fiendly AutoZone store, here's what you get for your 85 FWB's alternator IF THAT'S THE PROBLEM ( ! ).
> DuraLast 100 amp, Limited Lifetime Warranty, $78.49 +tax
> ValuCraft 100 amp 1 year Warranty, $74.99 +Tax
They don't show a core charge so I don't know if you have to give your old one back to them.
Happy wrenching.

N0DIH · #11 (**permalink**) 03-09-07, 01:07 AM

You can get a 140 amp alternator out of a 90-91 Deville without heated from glass at Autozone for $100 and a $75 core. It can be fairly easily adapted to the older engines (new connector for it and the older pulley).

carnut · #12 (**permalink**) 03-09-07, 02:32 PM

If this is a 4100 engine check the smog pump belt. Make sure its not loose, worn out. If the smog pump belt slips, the alternator will discharge when trying to recharge the battery. To confirm if the smog pump belt is too loose, try to rotate the alternator pulley the opposite direction of normal rotation with you hand, ENGINE OFF! If you can rotate the alternator pulley, the smog pump belt is loose, glazed or worn out. must be re tightened from under the car! This is correct for any 4100 engine with multiple belts.

lochenjons · #13 (**permalink**) 03-10-07, 03:25 AM

okay thanks for the help guys! ive been pretty busy and havn't really gotten time to take a look at it so tomorrow will be the day. ill keep you posted

The Ape Man · #14 (**permalink**) 03-10-07, 10:17 AM

Dunno exactly how they check alternators at awful parts stores. If the test does not load the alternator to the amount of current that the application (car) presents, it's incomplete. The test would also have to include at least 5 minutes continuous load at at least 1/3 rated current output. I've heard a few horror stories about how people had the alternator bench tested by the parts store (usually after buying a new one, installing it with a stone dead battery then killing the new alternator by charging the dead battery) only to be told it was OK. So now we have R&Red the alternator 3 times and we still have a problem. NASA rocket scientists all work at auto parts stores part time on weekends.

blackcadmatt · #15 (**permalink**) 03-10-07, 05:29 PM

Not ALL parts guys are full-time NASA engineers

Personally, I drink beer on the weekends and sell parts and equipment through the week

Definately the alternator, as the others have said. The output is easy enough to check with a multimeter. Red lead to the primary on the alt and black to the battery ground terminal. Anything less-than 14-volts with engine running, lights on, heater blowing, blah-blah-blah indicates a weak alternator on a GM. Usually it's internal regulator is the culprit.

If you go to Auto Zone or Advance, look for the guy/gal with the MOST gray hair as they will probably have the most knowledge under thier belt. I'm a sales rep for CarQuest and have gray hair too. When the alt in my '83 Coupe DeVille started acting up I just warranteed the damned thing

It helps to know your partz guy...