Battery drain?

Pat DiPersia

SCCoA Admin
So I took the SC to get inspected about a month ago. It hadn't been driven much before that. I keep it on a trickle charger (One of those smart ones, can't remember the name.) ALWAYS starts first shot like a champ, never dead.

Got it inspected and drove it around for the rest of the day. No problems starting. Brought it home, put it in the garage, and forgot the charger. Two-three days later, remembered the charger. Went to open the door and no lights. No nothing. Car was totally dead. Battery is about a year old. Odd. Really odd. I would think dim lights or something, but NOTHING.

Put a real charger on it for an hour, fires right up. Let it run for a bit, shut it down and put the trickle charger back on it. Few days later, dead again! ~~~?!

So I charge it for an hour again, fires right up. Shut it down and put an ammeter on it. With everything shut down, I'm drawing 2-3 amps - seems reasonable to me.

Now I'm wondering if whatever is causing a draw only happens AFTER I start the car? Almost like a relay is sticking or something? But once I pull the battery cable to put an ammeter on it, it resets and I only show 2-3 amps. Guess maybe I need a bigger ammeter which I can leave inline while I start the car.

Thoughts?
 
2-3 amps shutdown NORMAL??????? I don't see that being normal. Maybe 2-3 milliamps or even 20-30 milliamps I might buy.

Start pulling the fuses one at time while looking at the draw. Should be able to get it down to the circuit that way.
 
max key off current draw for these cars should be about 30mA MAX!! unless you have some fancy pager out of this world alarm fitted. 3 amps will draw a battery dead in no time.

like said before shut the car off and let it sit for about 30 min. then with out opening doors and disturbing too much pull fuses one at a time till the draw stops. then that should be your circuit that is causing you trouble.

my bets are the fuel pump relay is fubared and sticking closed causing that much draw.

I have also seen the relay/resistor pack for the blower motor stay on and the fan will spin slowly but not enough to move air and draw a battery that way.
 
Interesting. Never put an ammeter on a shutdown car before. Figured 2-3 amps for the various things that stay alive wasn't much. Guess I was wrong! Thanks for fix, I'll get on it ASAP!

Interesting on the blower motor. . .
 
2-3amps at 12v = something drawing 24-32 watts of power. That's more than what your interior light draws, and that'll suck a battery down in a day or so.
 
If you don't find the problem by pulling fuses, disconnect the power wire from the alternator. A bad diode in the alternator will cause the same symtoms you are getting.

David
 
If you don't find the problem by pulling fuses, disconnect the power wire from the alternator. A bad diode in the alternator will cause the same symtoms you are getting.

David

Good point. That's my next step. I just pulled every fuse and fusable link (Even pulled the relays for good measure.) Nothing. Though I did find the 60A fan fusable link is about to melt again - really cooked up. What's the deal - already on my second fan motor!
 
Good point. That's my next step. I just pulled every fuse and fusable link (Even pulled the relays for good measure.) Nothing. Though I did find the 60A fan fusable link is about to melt again - really cooked up. What's the deal - already on my second fan motor!

I had the same problem on my '94. I'll try and search for the thread where Dalke explained the actual issue. If I remember correctly, there is really no way to fix it without rewiring the fan 'circuit.

-Corey
 
Check your alternator

When's the last time you had your alternator checked? I got scrrreewed on one on a trip from Florida to Connecticut when the original one went south on a Sunday evening. $500.00 later for a "Life Time Warranty" alternator and a hard-die battery I made it home. I got home and let the car sit for a week and the battery was dead. Turns out, the alternator was junk and causing a voltage trickle. The alternator light never indicated an issue. I ended up calling the retailers corporate office to find out they don't have a "Life Time Warranty Alternator". So that's another story :p.

I ended up buying a G6 Alternator from some eBay seller. Here's the thread..
http://www.sccoa.com/forums/showthread.php?t=98495&highlight=bolt

Haven't had an issue since.
 
one time my ground was bad from the battery to the radiator support or whatever the panel is called next to the battery near the radiator , kicking on the fan intermitten even when car was shut off. i ended up running an extra ground wire from the battery to the header panel or rad support or fender fixed it. a couple years ago i bought a rebuilt alternator from advance , it always seemed to drain more than the original , it charges fine but with a weak battery i have to run it about every day or it will go dead , with a good new inerstate megatron it would prob go 5 or 6 days without running and be run down
 
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If you don't find the problem by pulling fuses, disconnect the power wire from the alternator. A bad diode in the alternator will cause the same symtoms you are getting.

David

We have a winner! I disconnected the alt, put the ammeter on there, and it was still registering between .3 and 2 amps. Bummer. Figured I'd let it sit for a minute to see what would happen, and sure enough, about a minute or two later, the ammeter dropped to .09 and didn't move.

Looks like an alternator is in order. Since the car is basically stock, I'd like to keep it that way - after doing some searching on here, looks like the original alt is no longer available? And the aftermarket stuff requires cutting up the connector on the alt? Any other solutions?
 
Find a local rebuild shop and have them reman the original for you. Doing that now with my spare unit here in MI.
 
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