m reg 405 diesel heater - jenodorf

Let me start by saying I hate cars. I have an M reg 405 diesel estate with air con and temp. selection. according to the Haynes manual it's the later type heater which has sliders instead of rotary knobs.

Ok here's my problem. If I put the temperature selector to cold the air con switches on but if I put it to hot only cold air blows. The heater matrix is hot and the Haynes manaul lacks any information. The control assembly contains an electronic board which seems ok.

According to the limited information in the manual the system is controlled by flaps and servo motors but I'm at a loss to locate them. My dealer has said that I'm looking at 10-12 hours labour to strip and diagnose.

Can any nice person offer advise as to where to look?




Value my car