My heater slider wouldnt move this morning from the cold section to the hot. It was very icy first thing and Im wondering whether its stuck? How hard is it to repair and how do I access it?

Under the bonnet between the engine block and heater box is the heater cable control. Make sure the metal clip is holding it in place still as this may have come undone allowing the cable to move but not open the heaters. That would be my 1st place to look.

Hope it's of some help?

Thanks, I have found a blue cable where you said which Im assuming is the correct one, it is attached to a rubber pipe? The clip is still in place so Im assuming its frayed or stuck at the dash end, what do I need to remove dash wise to access that end of it?

Here're some pics of the heater control cable attached to the valve (assuming you don't have an early car, in which case the valve is under the dash somewhere ...)




I'd guess there's dirt inside the sheath of the control cable which has frozen solid ... I've got the same problem on my mountain bike at the moment, can't change gear or brake

Cheers

Tom

Yes I've definately got the right cable, how would I go about clearing the dirt out? Can it be done from the engine side rather than taking the dashboard out!?

I guess any dirt getting in there would have come from the engine side, not within the dashboard (was there something involving your car and a beach recently? ).

Try spraying it with the stuff used to de-ice windscreens. Or wait for the weather to get warmer

Tom

Ok my man I'll try that although the MOT's due next Monday and my horn isnt working either so I'll get my mechanic to look at the heater aswell whilst he's fixing everything else for the re-test!

I've stopped taking my lovely 340 onto beaches, I need to look after her now as she's so damn reliable and good to me!

Try moving it when the engine gets up to temp. If you don't have enough anti freeze in the system then the water inside is freezing up on these cold nights and renders the valve useless until the ice thaws.

That makes sense, maybe there isnt enough antifreeze in the system althought the radiator filler tank has a bluey liquid in it and tastes real nasty!

Try heating each side of the valve, on the tubes, and the valve itself with a hair drier to see if it will free itself by thawing any ice in there. If the valve was set on cold no water flows through it and down through the heater matrix so possible not enough anti freeze in system has allowed the water in those pipes to freeze or with valve being closed anti freeze has not mixed through those pipes thoroughly to keep them from being frozen. Can be done by engine alone but does take time for those pipes to thaw so hair drier is quicker.

Leave some wd40 on it for a while, try that. Also your heater matrix might be full of sludge if you've not used it in a while. Might be an idea to flush it out, especially if your heat doesn't work once you've got the valve unceased.