Technical Heater fan not working 2007 Ducato 3000cc

[Peterpan44]

Good Morning,
My heater fan is not working on our motorhome.
I have stripped the dashboard.
There is power to the switch.
The switch has been tested and is fine.
The heat resistor thingy has been tested and ok.
The motor has been tested and works.


There is no power going to the heat resistor.
Could this be a relay problem?
If yes which relay is it as the handbook tells you what all the fuses are for but nothing about all the relays?


The dashboard has all been put back together now as we are going to France next week.
I have looked at the old threads on this subject but cannot find my specific problem.

 

[rayc]

Positive voltage is applied to the fan motor whenever the ignition is on via a fuse and relay in the engine fusebox. Negative is connected to the motor via the control switch and resistor pack. On high speed position the negative is directly connected as the resistor pack is by passed.
How did you measure that there was power at the switch?

I would check it out as follows. With ignition ON check the positive voltage on the fan motor with the negative lead of the meter on a known good earth.
Switch the ignition OFF and check continuity between the known good earth and the motor negative. it should be a short circuit with the fan position on High with varying resistance on the other positions [higher resistance the lower the speed setting.]

 

[Peterpan44]

Thank you for the reply. I will check everything next week that you have asked me as we are off to France tomorrow in the motorhome.

 

[Peterpan44]

Thank you for the reply. I will check everything next week that you have asked me as we are off to France tomorrow in the motorhome.

A year later and I have finally fixed the problem. Rayc commented on the same problem back in 2012 on a motorhome forum. I found it by accident this afternoon. The gentleman who had the same problem kindly posted a picture of the relay that powers the fan. I changed mine this afternoon and it all works as it should again. Only taken 12 months to fix the problem.

 

[BarrieAvis]

A year later and I have finally fixed the problem. Rayc commented on the same problem back in 2012 on a motorhome forum. I found it by accident this afternoon. The gentleman who had the same problem kindly posted a picture of the relay that powers the fan. I changed mine this afternoon and it all works as it should again. Only taken 12 months to fix the problem.

Could you post the picture of the relay please? (I think I might have the same problem.)

Thanks.

 

[HughJampton]

See this thread:

https://www.motorhomefun.co.uk/forum/threads/x250-ventilation-fan-faults-fixes.100160/

 

[Peterpan44]

The thread below posted by Hugh shows you everything you need.

 

[witzend]

Just removing the wire plug where it joins the heater and a good spray with contact cleaner fixed mine hope some one else may be as lucky