Unknown switch

[g8dhe]

As far as I can tell from the diagrams, yes, it uses a transistor and a bypass relay for the highest level here is the circuit;

Power transistor for Lo to Medium - G3-04 controlled by Pin 2D, then relay G3-05 comes in to bypass the transistor for Highest speed - switched by Pin 3P.

The transistor is located in the same / similar place as the resistors I believe;


The A/C unit also has a feed from the controlled side of the motor Pin 2E, so it could sense what speed / voltage is being applied, also it should be able to sense that the main control relay G3-07 has operated. Exactly what it does with the data is another matter - there isn't an internal circuit diagram to give that info.

In all there are three separate diagrams for the blower controls, the two above and a third simpler system for the rear A/C.

P.S Edit
- Just read the latest release of the Fact sheet and yes it discusses the two different systems and tells you that the transistor is a 2SD1525 device.

[JonWM]

Whoops.

Looks like i owe you lot an apology.
I have played with this switch now and it doesn't make a fan noise at all when switched on - i think the fan nise coincided with me having the switch on and then turning the ignition on and the AC was switched on.
Anyway, with the ignition switched on and no AC on then you hear the sound of a relay or something similar clicking when you switch on and off that switch. So it does look like an engine roasting switch - which i shall ignore.

Presumably I have this switch because the bongo came from a cold area of japan which may account for the rust on my rear wheel archs.

Jon

PS G8DHE - would you mind if I PM'd you wrt fault finding on the electrics?

[mikeonb4c]

Re: scavenger fan and over ride switch. My solution was very low tech as I'm no electronics genius

See this thread:

http://www.igmaynard.co.uk/bongo/forum/ ... r+fan+fuse

Re: Roasting switch - don't turn it on or MM will use it to roast me