Land Rover Discovery 1 faulty Cruise Control (pipe replacement)

Repairing Cruise Control hoses

My cruise control has never worked since I got my Land Rover so I decided to start to check it out and replace the parts of the system which are at fault.
After reading about the problems on several Land Rover forums it seemed the most likely issue was going to be the vacuum pipes which run from the vacuum pump to the back of the brake pedal and also the throttle position balloon (actually called the Cruise Control Actuator).

The most likely cause of the issue was that the pipes would be split causing the vacuum needed to set the throttle position would not work.  Effectively the split hoses would cause air to get into the system and therefore the throttle position would not be held.

Anyway, firstly you will need to locate your vacuum pipes and inspect them; they should look like this;

Discovery 1 cruise control pipes

The pipes are located, on the back of the throttle balloon/actuator.

Cruise Control Actuator, Discovery 1

 
Under the spare battery compartment, this is where the pump is.

Cruise control pipe replacement in Blue

They join on the left of the bulk head and there’s a T (see above) this will have a pipe going to the back of the brake pedal.  To get to this you will need to remove the trim.

Under the dash where the pedal are

 

Remove the trim clips using a trim removal tool

Yes the cruise control hose is in there above the break pedal

Check your existing pipes; if they are split you will need to replace them.

Old split hoses, the yellow one is for the garden

To do this you will need to buy replacements pipe about 4-5 meters, I bought mine for ebay for about £5.

New pipe above, old below.

 
You will also need a sharp knife and a flask of hot water or a kettle nearby.  I’ll explain this in a bit.
You will also need a trim removal tool as well to remote the panel at the passenger foot well.  This is to get access to the break switch.

Now to replace the pipes the procedure is as follows;
      1. Take one of the old pipes off
      2. Cut a new pipe to this length
      3. To fit it heat the end up in hot water and slide the pipe end on

You repeat this will all 3 hoses, the one at the back of the brake pedal will need you to remove the panel fasteners and feed a hose through.

New Cruise Control pipes fitted

All run neatly around the engine bay

That’s it, all done, it’s about 80% likely your cruise control will now work, guess what, mine did not.
So the next this I have to do is check the Cruise Control ECU and associated parts.