Battery draining - PCM?

[GreyAsp]

My battery has been draining pretty rapidly lately. I only drive about once a week and for the last 3 weeks it's been stone dead (alarm isn't even active) after sitting for the week. The battery tested fine after recharging, so I put a meter on it and found a 150-160mA drain. I started with the hi-current fuses and saw the drain disappear when I pulled #6 (Instrument Cluster/PCM).

Anyone have any ideas what could be causing this? I installed a Predator for the first time about a month ago... don't know if it's just coincidence.

Thanks.

 

[93 347 Cobra]

Is your alternator going south? Seems to be a common problem on Cobras.

My battery light has been flickering lately, luckily I'm having an extra overspun stocker rebuilt tomorrow.

 

[bakab1010]

ya mine was doing the same exact thing, it was my alternator

 

[rrpederson]

mine did the same thing after i bought mine, the alternator took a dump, i think it might have had something to do with the car sittin so long on the car lot. get the alternator checked out.

 

[badsube]

I had this same problem with mine. I think it was a combination of a few things. One, my alt may have been going south. Two, I think my mods may have been drawing from it even after the ignition was turned off, and third, I don't think I really drove it enough for the battery to charge itself enough to keep it completely charged.

 

[GreyAsp]

Oops.

 

[GreyAsp]

Ya, alternator was the first thing I thought of. But when I disconnected it, I was still reading the same drain.

I don't think it's from sitting... I've only driven it about once a week for the past 2 years and this is the first time I had to jump it.

Confused. :shrug:

 

[Dana]

How old is the battery?
It could just be getting weak.

A simple solution is to disconnect the battery the next time it sits for an extended period of time and reconnect it when you go to use it the next time. See what happens then.
If the battey is weak, it won't start the car or the symptoms will be the same as when it was connected.
If it does start the car, then you have a draw that you will have to find.

The draw you are seeing is not very big and the PCM and dash draw a small amount of current to maintain the memory in the computers.

You should probably use a Battery Tender anyway. This keeps the battery topped off between uses. About $50.
Dana

 

[mystic04]

Battery tender works great got one at pep boys for 30.00. my car wasn't driven of about 3 weeks back in october and battery died on me been fine after that . I will get a new battery being the orginal one is now 3 years old.