Land Rover Repair: Cruise control, vacuum hoses, vacuum tubes

Question
What's the most common cause of cruise control failure? The control of my LR (Discovery SE7 1998, V8, 4.0 L) is not working, I push the swith and light on botton goes on but it doesn´t work.
Thanks a lot for your help!

Ivan

Answer
First, you should make sure the vacuum hoses are OK. The most common problem is these hoses are cracked many place.
Check all the vacuum tubes whis goes to the cruise control's vacuum drum.
Second chance is the vacuum pump. It's under the left front part of the engine compartment. Under the hydraulic jack.
You can pull it out. There's no screws, but rubber holders.

When you sure the vacuum tubes are good, you should pull the tube from the pump clean it, take into your mouth and try to  suck it until the throttle opened. Now close the tube's end with your tongue. If the throttle is stay at the opened position while you close the tube, the hoses are good.

Than try the cruise control's working.