Common problem on KAs is a sticking heater control valve. Look under bonnet, central behind engine on bulkhead for the two coolant hoses that connect to it. Its electrically operated and can jam after a period of non use i.e set on cold all summer! A new valve is £25-£35 from a Ford dealer (they usually have in stock). It's not a big job to replace just a bit fiddly. Can be done from under bonnet in under an hour. Remove wipers, shorter one goes on driver's side. Remove scuttle trim screws (under plugs) and scuttle trim halves. Locate and remove screws that hold bulkhead trim in place. Remove passenger side trim. Not position of any harness clips and pipes. Move driver's side trim out of the way. Valve should now be accessible. Release hose clips with pliers/molegrips and slide off hoses. If stubborn, squirt some WD40 under pipe/valve joints, some coolant will be lost. Disconnect electrical connector. Valve hooks onto bulkhead. Fit hoses as they came off, use a small amount of copper grease on valve unions to ease this. Clips can be reused but if they are weak or break, replace with screw hose clips. Hook valve onto bulkhead. Re-connect power cable. Good chance now to clean all the accumulated muck from bulkhead area, the base of the windscreen and lube the wiper linkages. Replace trim in reverse order noting any cable/pipe routing and trim around valv inlet pipes. Remember wipers are side specific.
Hope this helps.
Danny B
November 2006
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