battery drain ... after rain?

First off, may I say this a great website, with some very helpful people - a great find. Next up, I bought a P38 1997 4.6 HSE and despite all the scare stories, am well chuffed with hit, having sworn blind in previous years that I would never buy a 4x4 - of any kind. This one is the nuts.

Anyway, I recently left the car in the drive for 3-4 days - got back in to drive off down to Focus DIY (I lead a very exciting life!!!) and all the door locks started going crazy, with the battery almost flat. It had rained in the mean time, so am wondering weather this may add any other issues in solving this prob. Have read previous threads on battery drain, and will defo follow them up .... any other suggestions in the mean time

many thanks

ok .... worked out that rain got nothing to do with it ... paranoia!! ... however, still looking for the gremlin!!!!!!! that said, I found a battery cut off switch which may prove useful until the overall problem is solved ...

Fix the gremlin - forget the battery switch.It would set the alarm off if you have a battery back up sounder on the alarm,possible keycode lockouts when you switch it back on again,and all those irritating beeps and messages to tell you the windows and sunroof arent set.If you cant get the EKA code into it to remobilise,your partner is going to love you to bits while you wait for the AA to pick you up !!! It does happen - on a regular basis.LP RR electrics can be very reliable - but only if they are well looked after.

cheers for the post .... you are of course right, so Ive got my multimeter to test out the battery and try and whittle down the gremlin .... im a total novice at all this, but Ill have a go ......

Hi, The batery drain is a common problem on the P38.

I have just reciently fixed the problem on my 2000 P38. It is all down to the RF receiver under the parcel shelf on the drivers side. It picks up signals from masts and in extreme cases even wireless doorbells etc. Draining the battery every time the ECU wakes up upon recieving these signals.

Land Rover has updated the RF receiver in 2004 and it works a treat, it will cost around £100 but it works and its the correct part without using any switches and messing about under the bonnet.

Hope this helps

James

As mentioned, the most probable cause is the BECM getting woken up by stray signals. Connect a ammeter to the battery (multimeter) and watch how much drain you have. From memory after 10 mins or so, it should drop significantly. I think Andy Cunninghams site has details of what the drain should be if the BECM is asleep.

http://www.cunningham.me.uk/rangiewiki/index.php?title=BeCM