Ah.. a transistor! so high impedance is normal.

So is this the circuit??


one terminal (+12)
|
<
> Resistor (100 K ??)
<
|....................................... signal (+12 or 0.6 V)
/
magnet------| transistor
\
third terminal (neutral)

So I need to connect a battery across two terminals and measure a switching voltage on the third.

So if sensor works, I put +12 V across two terminals and measured an AC voltage on the third>

Any idea which pin is which??

Paul

__________________
1983 500 SL (Gone )
1972 350 SL 4.5