Land Rover Repair: 2001 Range Rover LH rear will not roll down, service material, becm

Question
Just curious as to what causes this so I can know what I need to buy to fix it.

Answer
There are a few possibilities:

1) The wondow motor or lifter arm has failed
2) The window switch pack has failed
3) The BECM which sends the signal to the door has failed
4) There is a wiring problem in the door itself.

I have listed the possibilities roughly by order of probability.  As you can see, some testing is needed to decide what to replace or fix.

You can download wiring diagrams and service information from Land Rover's official site, www.landrovertechinfo.com

Note that you have to pay for this but the fee is modest and you have access to ALL official service material for your truck