Battery Drain

:welcome2:

I have a 2.5 diesel Range rover P38 i recently snapped the fan belt and had it replaced, the belt is all under tension i also had a problem with a brass olive dislodging itself from one of the cooling pipes under the vehicle i personally don't this this is the problem, it had been sat doing nothing for a number of weeks over the Christmas period. this of course drained the battery which is also just 5 months old and has been fine up until recently. Now every morning i come out to go to work i got to switch on and get all the usual lights that come up on the dash but when i go to turn it over it tries 1-2 times and nothing... new to this Range rover scene as this is my first and i'm only 21 years old so learning on the job any solutions to this post would be a fantastic help.

Checked/fine
-Checked all individual fuses under bonnet readings came back 0.02v when Becm is in sleep.
-unplugged radio
-checked alternator throwing out good/decent reading
- charged battery throwing out 12.05v
-no lights/interior left on
-Checked Becm on multireeder and watched it go to sleep and constantly stayed at very low reading for a long time roughly (10-15 mins)

Confused
-AA called out checked alternator/battery after jump start and on full load, reading came back as faulty alternator and to replace battery, checked at other garage and alternator was fine after vehicle had been running for minimum of an hour battery was checked and also fine.
-Getting small spark when connecting negative line to battery (may mean drain, may just be a normal spark of electric)
Have not tried
-Cleaning the earths but have read a bad earth can not drain a battery?
-Checking the rest of the fuses from around the car
-apparently if the Becm gets damp/wet this can affect it, so have not tried manually air drying this.

Worried
-one of the relays/fuses smells like burning plastic from the fuse box under the bonnet.
-The car has a damp issue could this be a problem

Thanks Matt

try a search on alarm and rf wire

:welcome2:

As above...the P38 has a dumb RF reciver for the alarm and it picks up stray RF signals....it then wakes the BeCM (Body Electrical Control Module) to see if it is the right code to unlock the car....the BeCM tells the RF unit to p!ss off and stop being stupid and 3 minutes later the BeCM goes back to sleep again...only for the RF unit to wake it up to try out another stray RF signal...and the cycle begins....

This constant waking and sleeping of the BeCM can flatten a battery overnight in the worst case or a couple of days if your battery is half decent.

Temperorary fix is to remove the blue aerial lead to the RF unit (your key fob range will be reduced) and then you can replace it with the 3rd generation RF receiver which is much smarter.

The P38's do suffer from Fuse box failure and one of the first signs is a smell of burning from it....this can cause allsorts of electrical issues....replace as soon as you if you smell a burning smell or bluing of the contacts within

12.05 volts means the battery is less than half charged borderline flat. after charging and resting for 30 minutes you should see between 12.5 and 12,8 volts. If the battery was left discharged for several weeks it's almost certainly knackered.
With a good battery and the engine at 2k rpm you should see 14.2 volts at the battery.

Okay thanks guys still mo luck as I have to keep disconnecting the battery just to be able to use the car.

Thanks matt

1 other thing is I do not actually have a FOB with the car it just works off key, if I was to get a new fob and set he code in would this also help?

Thanks matt

lambden said:

1 other thing is I do not actually have a FOB with the car it just works off key, if I was to get a new fob and set he code in would this also help?

Thanks matt

Click to expand...

They are meant to work off the FOB. I would suggest a new FOB which can only be obtained from a dealer and a new RF receiver.