Bongo Fury

Hi, quick question about how the fans work. In my Bongo the fans don't seem to start until I turn it to 4, at which point they come on full blast. Does this sound right?

The air con also only seems to work when it's pointing to 1. There's a light on the air con button which comes on when I switch it to 1, it then goes off if I turn the fans higher. Again, is this normal?

Any help much much appreciated. Perhaps there's more hot weather coming?!
Stu

The fans only at level 4 makes it sound like the Climate Control type (electronic) and where the speed control transistor has blown, on level 4 the transistor is bypassed by a relay for full speed. If its the older style, then all the thermal fuses bar the fastest speed have popped! and need soldering back down again!
The transistor is available here http://nikkoe.com/catalogsearch/result/?q=2sd1525
and the module is under the middle of the window screen under a cap behind the X02 fuse box - red arrow.

oh thanks for the detailed response Geoff. I'll have a crack at this myself...
Cheers!