Blower resistor swap

[HORCH]

My heater blower in the cab has only worked on full speed for a long time, in the S2 and my 80 tdi.
I couldn't find a new right hand drive resistor but found plenty left hand.

Imagining that it would only be the panel the resistor mounts to that is L/R handed, I thought I'd remove the resistor from a left one and solder it to the right handed panel.

So I've done this but have noticed the diode that is connected to the two prongs is now the wrong way around, which is a given because its the opposite.

I also imagined I might have to change a swap a couple of pins in the connectors.

Does anybody have a wiring diagram for the blowers for left and right hand drive cars so I can make sure it will be connected correctly, or is everything on the left hand cars completely opposite?

thanks for any help

[johne]

The item you're calling a diode isn't one. It's a thermal fuse. It doesn't matter which way round it is connected.

The resistor pack never fails, LHD or RHD, what happens is that with age the blower motor starts to slow due to friction building up due to lack of lubrication for its bearings. The motor draws more current which causes the resistor pack to heat up more and blow the thermal fuse to protect from a melt-down just as it's designed to do.

Once the fuse blows you just get left with full speed or nothing.

Replacement thermal fuses are readily available. Iirc, a value of around 120c will do but it doesn't have to be too precise.

Solder the replacement in with care!

Your original RHD pack will be fine with a new fuse so you don't have to worry about LHD/RHD ones but do replace or lubricate your heater fan motor bearings or you'll be back at square one.

[HORCH]

Johne, thats brilliant knowledge you have, I wish I knew before what I know now hah, I'm kicking myself,

I fitted it and it did work but it would have been much more professional just changing what I thought was a diode,

I have also removed and oiled the bearings in my blower but will try and find a new one.

would a left hand blower work as thats all I can find.

I'll do the job properly on the S2 though!

thanks Johne I'm really grateful

[johne]

The fan housings are handed between LHD & RHD but I don't know if the fan motor facing plates are. At worst, you could remove the replacement motor from its LHD plate and swap it into your RHD plate to replace the motor.

Also note you can buy a new fan motor from Autodoc.co.uk from £20 upwards, depending on which brand you choose. I'd go for Valeo, an OE brand at nearer £35 but still better than S/H.

Also, iirc, the fan on a car with AC is bigger than the fan on a non AC car, suggest you use LLLparts or similar to check.