need to know age of your fiesta im guessing its 96 onwards.if it is i suspect its the heater control valve on the bulkhead.its controlled by an electric motor that packs up.part costs about£36 and is 15 mins to fit.
k, October 2004
there is an electric valve situated under the bonnet if you follow the heater pipes you will find it next to the wiper motor it is not repairable but is simple to replace hope this helps
