'04 Mondeo Strange Heater Fan Fault

[ModishNouns]

Hi All,

When I turn the ignition 9 times out of 10 the heater fan comes on full blast but the heater controls and display are all dead. If I turn on the head lights, the heater controls wake up and the fan reverts to its proper settings.

It doesn't seem to matter what the heater / fan / A/C were set to. It doesn't even make a difference if I turn everything off before killing the ignition when I leave the car.

Any ideas?

[Seand8288]

ModishNouns i have the exact same problem! I was wondering did you find out what the problem was? Its doing my head in! Ive searched the internet inside out and you are the only one ive came across with same problem.

Edited by Seand8288 on Wednesday 14th December 22:51

[ModishNouns]

Hi,

I haven't sorted it. I'm still using the lights

From reading around I couldn't find anyone else with this exact problem but there are issues with the wiring loom for the heater controls behind the dash burning/shorting out and causing odd heater behaviour. I haven't got round to ripping my dash out to investigate, though.

[Seand8288]

Its def a strange fault! When i get the time, i might take a route around behind the dash to see if i spot any problems. I'm thinking about selling and would love to get the problem fixed before i do. I'l post back with any news sure..

[Seand8288]

I got the problem fixed eventually! The heater control panel in the dash was faulty. I just replaced it with a salvaged part and hey presto, it cured the problem. When i took the faulty one out, i was expecting to see some corrosion on the circuit board or even a burnt out wire on the loom but everything looked fine. I was doubtful that the new part would fix the problem but it did. Seems strange now getting into the car and not having to flick the lights on and off to turn the fan off! So glad to get it fixed. It was a bit of hassle removing the heater controls but well worth it in the end.