Electrical/ battery drain troubleshoot

[rooster]

Jr. found him a 94 olds cutless for a get around car! 100 bucks asis! Its got some electrical problems , it drains the battery after a few days sitting. After reading some post in the archives for the troubleshoot we connected a volt meter between the neg post of new battery and the neg cable, it shows about 12 1/2 volts, this is with the doors shut and the light bulb under the hood removed. the radio has been removed so there is no
clock. My understanding is this should be zero! We disconnected the wire going to the alt still no change in the reading, we then disconnected each fuse 1 at a time looking for a change in the reading on the volt meter,
no luck!
Any ideas were to check ?  

Known electrical that dont work: interior lights, door locks ( no fuse), horn (no fuse),.

[MrMopar64]

Well I'm not positive but I think is what you want there is an amp meter
Because with volt meter to ground your going to show battery voltage

But I could be wrong.....  

MM64  

[Crosley.In.AZ]

a 94 will show a small drain on the battery since it has a computer memory to maintain.

[Pep]

If you're looking for a battery drain, then you need to place an ammeter in series with the positve lead. I am talking a multimeter set to milliamps....but don't turn anything on or you'll blow the snot out of it. If there is only low milliamps being drawn, then all is fine. Initially set the scale to high amps then slowly come down until you get a reading.

[EMSjunkie]

I'm gonna throw this out there, 'cuz it happened to me.

Does it have electric seats?
I had a 69 Pontiac Grand Prix SJ that was doing the same thing.
the seat adjusting lever was sticking, found it by accident, leaned down to pick up a dropped screwdriver, and heard the faint whine of the motor

'course that was back when I could hear :oops:


Vance

[rooster]

No it does not have ele seats.

It does have ele door locks though, As I said earlyer the door locks dont work but when we disconnect the battery we can here them clicking (alot) we have not found a fuse for the door locks, we will probely take a look at them first. It sounds to me that I shouldent hookup the meter in fear of burning it up.

[stude55]

Dont know what gm spec is but Ford says no more than 50 miliamps. Why dont the interior lights work? Is there a module that controls interior lights? If so unplug it? Had a 92 Olds ninety eight, If I remember right, I had a bad drivers door latch, it was not turning off the cluster and I think the radio, when you turned the key off the cluster and radio stay powered up until it see's a door ajar signal. If your door ajar switch is bad, things dont power down, and interior lights dont come on(when the door is opened) My car was a beater and the ajar switch was only available from the dealer as a latch assembly, so I isolated the wire at the latch and hooked up a momentary switch to ground. As long as remembered to hit the switch when I got out everything was cool.

[58Apache]

I have seen a lot of weird things over the years working with electronics. From corrosion causing a partial path for limited current flow, to partially pinched wires, and everything in between.

Go out on a dark night and see of you see any lights on. It's possible a trunk light, glove box light, or under-hood light is staying on even when the doors are closed.

If you're afraid to use a meter for measuring current flow I have heard of some guys using a cheap light voltage tester put in between a battery cable lead and the battery terminal.

If that don't work, disconnect your alternator and see if it still drains overnight.

What's the voltage at the battery with the engine running? it's possible you may not be getting much of a charge from the alternator.

Finally, just because a battery is new doesn't guarantee it's good. As was said, you will get some drain no matter what.

                                  Steve

[brti]

I've changed may be 10 batteries this year on various machines and all were sulphided and wouod not hold a charge. It would take several hours to several days for them to die. Try a battery tester and see.

[donsrods]

My ex had a Lincoln that would start fine during the week, but would drain on the weekend because it was not getting started every morning.  Found out it was an internal short in the battery, between the plates.  Replaced battery, no more problem.

The alternator is another source, as mentioned.  I think a diode goes bad, and it backfeeds.  Go to Autozone and let them put it on their handy-dandy tester.  It should pinpoint charging, starting issues, and maybe even the condition of the battery.  The test is free, too.


Don

[model a vette]

I believe a '94 Cutlass has a similar setup as my son's '92 Lumina so I'll give a few insights to GM's attempt at 'lectronics EVERYTHING:

I believe the seatbelts are mounted to the doors. There are sensors and solenoids in the doors. Sometimes the solenoids "click" and cycle when they feel like it! A sticking one may cause a draw.

There should be a module that delays turning off the radio and interior lights as stude55 mentioned.  I think this may part of the headlight switch which is why the headlight switch is so expensive.

The alternators in these cars have a habit of going weird. My son's car has had at least 3 since 1999.

The car would die without warning and would have NO power. A jump would sometimes get it on it's way. I searched the 'net and found a "W" body site that had several threads about power problems. I went with the cure that some had used to chase the gremlins. I ran a 10 gauge wire from the large alt battery connector directly to the remote positive battery stud, thru a fusible link. (The battery is buried so there is a connector on the driver's fender.) It looks like all the problems went away!

I looked at the wiring diagram and the battery power goes thru a bunch of connections before it gets where it needs to go. The battery cable goes to the fender connector. The power then goes to the starter lug where it joins several wires going to the two fuse boxes. There are a couple of fusible links thrown in also.

Good hunting!

Ed

[GPster]

Jr. found him a 94 olds cutless for a get around car! 100 bucks asis!

Maybe this answers the question,"why only  $100.00?" GPster

[rooster]

Thanks for all the input. I placed a meter between the positive bat post and pos cable , meter set to 200m the reading I get is "3.2", this is with the doors shut, no key in ignition, no clock or radio, bulb removed from under hood, alt disconnected!

I suppose this means the system somewhere is drawing 3.2 amp from the battery!

From some of the stuff im reading a draw from the battery with everything turn off is called "Parasiti draw". Im not sure of this but how much draw should I expect to be normal?

To answer some of the questions:

The doors have seat belt attcheted to them and could have been the nose we heard when disconnecting the battery, instead of door locks.

With the engine running the alt is charging 14 1/2 V.

I have no idea why the dome light dosent work.

The head lights, windows, blower moter , turn signals, car starts and is driveable, only the door locks,horn, and interior lights dont work.

I dont have much history of the car, but was told that it drops dead while driving. Could be just from the battery so run down!

The reason he got the car so cheap was because of the electrical problem, the junk yard was going to give the guy 150 for it , if he dove it to the yard. Son made a deal for 100 asis where is. Now its in my driveway.

The 2 front doors do no have button switchs that get pressed in when you close the door, but the rear do.

Next test is to remove all the fuses and test again with amp meter, to see if there a change in reading.

[Pep]

Thanks for all the input. I placed a meter between the positive bat post and pos cable , meter set to 200m the reading I get is "3.2", this is with the doors shut, no key in ignition, no clock or radio, bulb removed from under hood, alt disconnected

From what I see, you had it set for the 200 milliamp scale. With a reading of 3.2 milliamps. That is insignificant. If you were drawing 3.2 amps, then you would notice a fairly hefty spark as you removed the terminal.
The 14 volts charge is fine, so the alternator is OK. This leaves 2 things.
1. The battery is crook
2. There is a ground issue between the block and battery.

[model a vette]

"I dont have much history of the car, but was told that it drops dead while driving. "
Re-read my post about how to cure "drops dead while driving". Run a wire from the alt battery post to the battery pos with a fusible link to protect it.

"Could be just from the battery so run down!"
Once the car starts it will run off the alternator (which is working because it has 14.5 volts when the engine is running). A low battery USUALLY won't cause it to drop dead.