Land Rover Repair: battery drain

Question
QUESTION: Hi,
I have a Disco 2 from 2000 with a slow battery discharge. By process of elimination, the battery stabilises when fuse no. 13 (BCU) is removed from the engine fuse box. That fuse seems to affect a load of other circuits so how best to proceed?
I also have 3 warning lights on the dash which will not stay off even when reset by the garage (who said there was nothing wrong) hill descent, ABS and handbrake. ABS with red light other two amber.
I guess that is two questions - hope I am the only one today!
I try to do what I can because garages here in Norway are very expensive and landrover is not very local to me.....
Thanks
Keith Richardson.

ANSWER: If the warning light continues to come on that means there is a problem.  Lights do not come on just to be reset.  My guess is that the garage lacks the tools or the skill to determine what's wrong.  There is no such thing as ABS warning lights with no problem.

As for the battery drain . . . you are going to have to get the wiring book and disconnect the potential draws one at a time till you get to the bottom of it, assuming the BCU itself is not the problem.  

---------- FOLLOW-UP ----------

QUESTION: Is there a way to check each circuit without having to wait several hours to see if the battery drains? Exact proceedure in detail please! I am hesitant to ask the garage to investigate because I fear they will clock up a load of hours faffing about.

Answer
Yes, what you should do is put a clamp on amp meter on the circuit and measure the drain.  Normal drain is about 0.030 amp.  If you find - for example - .400 amp drain, that is your problem, and you would disconnect circuits one my one till the draw goes away.  The shop should know how to do this - it's a fairly universal electrical troubleshooting procedure - and if they don't I would look for a place where the staff are a bit sharper