It's taken me a while to write this, and sorry it's in the form of bullet points (I'm at work and rushing a bit). I've assumed everyone knows the spare wheel needs to come off and you can do this job lying in the spare wheel carrier (it's not comfortable so I hope you do it faster than I did)
. First, you don't need to take the dash out. Just the heater control panel, the stereo and the lower cowl just in front of the gear lever (we have a manual gearbox RHD van). It helps to take the instrument binnacle cover off to get more light on the job but it's not vital.
. If you're replacing a cable, it's a lot easier to pull it out from inside the cab. You'll need to unhook the end of the inner cable that is secured to the heater control valve under the van. You'll also need to remove whatever is currently securing the cable sheathing to the valve. It could be the original spring clip or a cable tie (which I had and which can be a bugger to cut off). At the dash end, you'll need to release the 6 mm bolt that holds the sheathing in a clamp before you can unhook the cable from the heater control lever. If you have a 6 mm spanner, it will make the job easier. It's too tight a space to work in with a socket.
. As far as access to the valve goes, I had a cable tie around the supply and return hoses to the heater matrix. I cut that off. There was also a cable tie securing both hoses to a strip of metal next to the gearbox linkage housing. I cut that off too. That gives better access to the valve and cable.
. You're working very close to the cooling fan, so at the very least do this job with a stone cold engine or better still disconnect the battery.
. Once you've pulled the old cable (and its ribbed outer cover) all the way out, feed the new one in from the cab through the rubber grommet in the floor. Don't try to feed the ribbed outer through the grommet because a) it's a struggle and b) it makes the cable harder to locate on the valve. Don't feed the rest of the cable behind the dash at this stage - leave it floppy to make attachment at the valve end easier. I know my photo shows it with the ribbed outer shoved in the grommet - that was someone else's work...
. If you see the photo with the two hoses and the valve (above), it helps to have the front of the valve (with the lever) as close to horizontal as you can so that you have the cable straight sitting across the valve. The 'kinked' end of the cable attaches to the lever as you can see in the fabulous photo I've borrowed from
Cardomain.com. I've not bent mine - just kept it as you see it here. I've failed spectacularly (twice) to get the proper clip (available from Brickwerks) to fit so I've used a heavy cable tie. I've not nipped it as tight as I can yet (the sheathing moves a little bit) and I'm letting it bed in before I do that. At this end of the clip as you see it in the photo, there's a slot in the valve and threading even a quite beefy cable tie (the wheeltrim ties from Wilkos are perfect) is not so hard. I'm clumsy. I've looked at this photo often - it's a great help when you're testing.
. Back in the cab, pull the rest of the cable through behind the dash, over where the stereo head unit will be and try not to twist the cable as you pull it to the lever. The cable as supplied has a little kink in the 'cab' end which would hold in an ideal world. However, to fit it like that, you'd need to go in from above and then access would be a headache. If you can see from my photo, I bent the last 4 mm of the cable 90 degrees and it drops into the hole in the lever from above and works ok. It's very important to clamp the cable so at least 20 mm of the sheathing protrudes beyond the clamp and into the heater control opening (does that make sense?). That bit really is critical, or you'll have a heater control that springs back from the 'cold' setting and does nowt! First photo shows how your cable may look when new and second photo shows how I bent it. You'd want to do the same, I'm pretty sure.
. While my 'fix' settles down I'm leaving the heater control panel off and I'm using the heater control gently so the cable doesn't pop off either end. Two weeks in, it's looking good.
I hope that helps someone - bit of a labour of love. Any comments welcome.
Cheers
Chris
Update 4 October 2015
I finally got round to refitting the heater control panel, knobs and rotary blower control today. Not because I thought the fix wouldn't work, just plain old laziness. A couple of tips:
* I smeared a little vegetable oil on the two pins that locate the heater control panel in the dash (by the way, the pins are bottom left and top right of the panel to help you when you're taking it out). I also smeared some on the control levers to ease the knobs back on. Can't see any point straining things more than absolutely necessary.
* To make it easier to get the knobs back in place, I placed the levers so they were not aligned one above the other, but not too fanned out either - you want to be able to see them all. I only located the pins on the control panel back into the dash once I had the knobs most of the way back on the levers. The I secured the control panel, brought the levers to the central position and pushed the knobs all the way onto the levers.
Sounds a bit OCD but it makes the job a lot easier and reduces the chances of breaking the heater control panel -I've not seen any for sale anywhere!