Ford Ka (old shape) - Heater not working

[3sixty]

The OH's Ford Ka has decided that it doesnt want to blow out hot air.

The vents do work, but are constantly cold no matter what fan speed or temperature selected.

I have replaced the fuse/resistor in the passenger footwell and the heater valve, but no luck so far.

Anyone any ideas short of me taking it to Ford for diagnosis?

[bu88ski]

depends on if the controls are cabled or electronic. if cabled check the cables for breakage or loose / uncoupled ends.
if elecronic where the connector plugs onto the heater control valve by the matrix check the connecting cables are receiveing volts/current when someone turns the dial. bear in mind that the signal may only be for a second or 2.

i had an issue with my fiesta doing the same thing and all it was was a seized valve on my HCV. I did do read outs on the signal cable to it and the supply is 2 way so one way you will see a + voltage and the other way a - voltage.

hope this helps.

rob

[Karlos TDCi]

I had a similar issue on the Wife's Fiesta so I changed the HCV and drained the coolant before refilling with fresh stuff. I still couldn't get hot air from the heater matrix, but realised I had some sort of air lock or stuck HCV. I switched the engine off, disconnected a pipe from the HCV, reconnected and it worked!