Something is obviously drawing down the battery. 1999 S70. If the car sits for a few days, the battery goes dead. Put test light between positive terminal clamp and post. Lights up, so something is drawing power with the car off. Pulled fuses out one by one. The light goes off when the fuse in position 8 (15 amp fuse) that is for "light switch, immobilizer". With the fuse pulled, car won't start, just cranks. With the fuse in, car starts fine. Any ideas???

 

maybe a short in the circuit where that fuse leads to. and it seems your car needs whatever is behind that fuse to get power when you turn on the car. Maybe your light switch? I don't know how the immobilizer works.


.....but consider yourself luckyI have a similar yet worse issue.

My 99 s70 t5 draws battery but only sometimes, which sucks. Sometimes in a week it'll happen twice and then it wont happen for a month. It's occasional, and I'm currently trying to do the same(check with a circuit light tester) but the light isn't staying on and the car isn't drawing again. I know it'll come back when i dont expect it, it's a real pain in the a-s, and I need to catch it on a day where it's drawing again so I gotta test it every day. very annoying.

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