Nissan Sunny - Battery Keeps Going Flat

[pacuk01]

Hi,

My mother has got an aging Nissan Sunny. Been a very good car. But over last couple of years it has had a problem where battery seems to go flat in cold weather, and the car wont start. Replacing the battery has usually seemed to cure this until this year.

I have put on a new battery. Car goes flat after 4 days if damp and cold. I replace this new battery as it might have been faulty. Still have same problem. I test the drain on battery when car is engine and ignition is of and decided that the small drain on the battery might be caused by a faulty alternator. I fit a new alternator, the small drain on the battery now goes away, but after four days of non use the car still goes flat. I am running out of ideas. I understand there might be an intermittent power drain on the battery which is enough to make the car fail to start. How will I find the fault. or will it just be easier to fit an isolator to the battery to stop the drain. It is obviously an electrical drain - All doors are shut and the lights are out. I was trying to think of which circuits have power even though the igntion is off. There must be power to internal lights, Central Locking, Clock...anything else??

I am at the end of my tether on this one, and so is my mother.


Any help please?

[la1]

when you do the drain test pull one fuse at a time till you find out what is draining. pull the fuse then look at the DVM

[pacuk01]

The car has arrived at my house, and straight away I put an amp clamp over the negative cable and the drain on the battery was 0.2amp. I removed a relay numbered 25230c9962 12v 80118H as I noticed it clicked every time I reconnected the battey, it shows on the cover "LAMP CHECK AUTO CHOKE" the relay also felt warm. The key was not in the ignition. Directly I removed the relay the amp clamp went back to zero. Now is the relay faulty, or is there a fault in the supply to the relay, or is it a red herring?