Identifing A Component, fan speed control module

[g717xnm]

Hi all,

I'm trying to repair a fan speed control module. I have the transistors but need to know what the resister like component on the other side of the board to the full speed relay is . It has the following numbers on it R5E474 mlc 010. Any one got any ideas?

Thanks
Chris

[xmexclusive]

Hi G717xm

The one on my spare pcb has the same markings. It looks like a polystyrene capacitor to me rather than a resistor. I would be surprised if it was suspect.

Regards

XMexc

[g717xnm]

My speed control is a bit older than the one in the help files. the polystyrene capacitor is soldered on to one of the rivets and the leg of the transistor. It got damage when i was taking the speed control out. oops!

Does anyone know where i can buy a 0.5 uf polystyrene capacitor from as i only need one!

thanks for your help

[xmexclusive]

Hi G717XM

Have just had a look in some of the electronic component catalogues that were handy. I think the beast is actually a Monolithic Ceramic Axial Dipped Capacitor. As far as I can see you are right with the value as .47uF. Maplin only stock the Ceramic version with parallel leads instead of axial (part no. RA52G @ 11p each). Cannot lay my hands on the RS or the RAPID catalogues to check if they supply the axial version of the capacitors. These capacitors are not polarised so it does not matter which way round they go.
Out of interest what type of replacement transistor are you fitting?

Regards

XMexc

[g717xnm]

I'm using MJ11015. RS part number 295-163. I got this info from this months Citroenian (citroen car club mag) sorry to say still learning and working things out on the way to keep my xm on the road!

By the way do you know the perpuse of the capacitor. As mine was a retro fit what problem did it solve?

Thanks for your help

Chris

[bigjohnh]

Hi g717xnm,

If that capacitor was attached to a transistor leg it was probably be there to prevent any nasty noisy voltages from the motor damaging the transistor (They don't like it up em). Capacitors tend to fail short circuit which would either fry the transistor or, if the circuit is clever, just stop it working. Either way it would stop the motor running until fixed.

Hope this helps

John