Land Rover Repair: AC BLOWER FAN PROBLEM, electronic speed controller, alternate power source

Question
QUESTION: I have a 04 Discover (front AC only)and the AC blower stopped running or so I thought. I took it to a shop and when they hooked up an alternate power source the blower worked fine. The power plug at the blower motor reads 12vdc (on the truck side of the connection) but when it's plugged into the blower it only reads 4vdc on the blower side of the connection. That lead us to believe that the blower could possibly be shorted but again when hooked to another power source it works. We then began to suspect the AC blower relay, which we attempted to swap out but didn't have land rover relays. As we disconnected the relays to test them we could actually hear the relays click when we reconnected them. It's hot and I'm ready to try anything so what should I change first? Also note that the blower doesn't blow in any mode including defrost.

ANSWER: I would say you need a fuse box or an AC control module.  You might also have a wiring problem, and no bad components

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

QUESTION: All of the fuses are good and the power on the vehicle side of the blower motor plug also appears to be good. Are you talking about the AC control panal in the dash or is there a computer module located somewhere else? Someone else was telling me the problem is likely the AC motor resistor, do you where its located and could cause this type of problem?

Answer
That car uses BMW 740IL climate control, and in those cars the problem you have would point to the electronic speed controller which is located on the side of the blower, or the dashboard control unit, the one you push buttons on.  The other problem area can be the power distribution from the fuse box as I suggested


Hope that helps