I have a 1996 RHD Defender 110 with factory air con. So it has a climate control unit in the center of the dash (not the levers). I removed the climate unit to run a wire behind it and when I was putting it back together the fan/blower speed switch stopped working. The blower does not turn on anymore. Not sure what happened but looks like a connection issue somewhere.

Any suggestions on how I should start to trouble shoot this?

 

Did you check fuses?