Need help with Caddillac battery draining.

[Flyingchipmunk]

I am hoping that somebody can lead me in the right direction with this problem.

My brother's Cadillac a 97 STS has been losing battery power rapidly after you shut it down. If I try to start it right after I shut it down it starts with no problem; I checked the battery voltage and got 13.xx. I checked all the lights and have been going through fuses with the voltmeter to try and find something that is drawing power with the key off. Less than a half hour after shutting it down the voltage is down to 9.8v.

Other than the trouble shooting I have been doing; the only other thing I can give you is that the Inadvertent power relay was making a humming noise the other night after sitting for a bit (probably confused due to the lack of voltage??).

[jcormier89]

altenator not charging the battery?

[oleshifty]

let it run for a while. turn it off. disconnect cables. Check voltage couple hours later.

make sure car is actually drawing power....could just be a bad battery (most autoplaces can charge/test it for you)

i believe standard draw on most newer cars is like a constant 15mA to run computer/radio memory/etc.

[txarkitekt]

altenator not charging the battery?

+1. Possibly.

let it run for a while. turn it off. disconnect cables. Check voltage couple hours later.

make sure car is actually drawing power....could just be a bad battery (most autoplaces can charge/test it for you)

i believe standard draw on most newer cars is like a constant 15mA to run computer/radio memory/etc.

+1.

[GasGuzzler]

Up to 100 mA can be normal depending on vehicle contact and battery amp/hour rating.

I don't have paper manuals for Caddy and online service information starts at 1998 but I can try to help....

You really need a meter that can measure amperage up to 10 amps. Also, make sure you are familair with it as connecting or disconnecting components or meter imporperly can ruin the meter or blow expensive and hard to find fuses in the meter.

Once you get that handled, remove the 50 amp INDVERT fuse underhood. If the draw goes away with the fuse pulled, put it back and remove the SEATS circuit breaker and recheck.

Do all of the seat functions work? If not, it is possible one of the seat switches is stuck in a up/down/in/out position. Lumbar is most common.