Alfa 33 4WD -91 - 4x4 problems

[Erkki Tuisk <erkki@domain.elided>]

Hi Alfisti,

I am new owner of used Alfa 33 which has quite rare 4WD (at least here
in Estonia).
Does anybody have any idea how the 4WD system generally works? 
There is a yellow signal lamp "4X4" on the dash and it is shining
continiously. 
>From where and how it checks if the 4 WD is on or off? What could be the
main problem with that? Previuos owner told me something about "magnet"
what can cost about 2000 USD?
When to turn ignition on, then I can hear a metal click from the gearbox
area and the above mentioned lamp blinks for 0,5 sec.
Local Alfa Represenative is working here on very low quality and service
level, so they do not have even a book about it!

Any info could be a big help!

Greetings from snowy Estonia!

Erkki
Alfa 33 S QV 1.7 16V 4WD -91
Alfa 164 3.0 V6 -89

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