C5 Mk1 facelift blower fan doesn't work properly

[Tsunami]

Hi all,

I have 2005 Citroen C5 2.0HDi sxpk mk1 Facelift. My air blower doesn't work when inside temperature is too low (nearly below 5⁰C). When inside temperature increase because of breath or something else, it starts to run. Where must i start to solve this issue? I have searched about fan resistor or driver but facelift models don't have any seperate controler like mk1's.

Thanks in advance.

[GiveMeABreak]

I think you'll find that the blower control module on these are built into the actual Blower Motor, so are not separate.

[Tsunami]

How can i find the problem? Can you mark the possible components?

[GiveMeABreak]

Not really, as it's a different design to later vehicles, hence the need to replace the complete unit as far as I can see. These are no longer available new from Citroen incidentally, but that circuit board looks to be in a bad way for a start.

Maybe a gentle clean up with some electrical contact cleaner may help?

[Tsunami]

I couldn't find brand new blower unit, it is only available as used and pug 407's blower. I don't want to change unit with in unknown condition one.

For board, there is some dust on it. Nothing seen as blown or broken. By the way it is already working when the ambient temperature is hot enough.

[GiveMeABreak]

That may suggest a dry solder joint then. As the ambient temperature warms up the joint expands and makes contact and then contracts when cold.

[Clogzz]

That may suggest a dry solder joint then. As the ambient temperature warms up the joint expands and makes contact and then contracts when cold.

That will be for the large output transistor at top left.
The electrolytic capacitor at top right is also likely.
They very often don't work when cold and recover as they warm up.
Replacing electrolytic capacitors has kept me off the streets for a lifetime.

[Tsunami]

That may suggest a dry solder joint then. As the ambient temperature warms up the joint expands and makes contact and then contracts when cold.

That will be for the large output transistor at top left.
The electrolytic capacitor at top right is also likely.
They very often don't work when cold and recover as they warm up.
Replacing electrolytic capacitors has kept me off the streets for a lifetime.

Thanks for the answer, i will change the capacitors. But i will see result may be a month later. Or is there any way to run blower on the desk? If yes i will put it to refrigerator

[Clogzz]

is there any way to run blower on the desk?

No unless you can cobble an extension of the speed control wires because the fault is in the control module.
If the existing wires are long enough you can dangle the lot where you can heat the module with a hair dryer.