Hi,
I have a VOLVO s70 1998 2.5 petrol with the battery going flat. I had the battery and the alternator checked and they are ok. If I jump start the car it starts ok but is flat in the morning. Any ideas what could be causing this drain. Thanks

 

look for a parasitic drain or bad connections. RSPI has a really good video on fixing the battery terminal. it seems there are a number of issues popping up for a failure of the wire-to-clamp crimp. Soldering seems to help. If it does not, follow his battery debug video.

 

 

I had this problem. It turned out to be the wire coming from the firewall that connects to the positive wire. The nut was the wrong size and even though it was tight it wasnt holding the connections together. Not trying to point out an obvious point but sometimes we tend to over think things. I was annoyed, the answer was in front of me the whole time.....

 

Yep, ck for parasitic draw. Common culprits are someone left the trunk interior light switch on, or the glove box light switch not being closed fully..