I have an In-Lite transformer (220VAC-12VDC) that only puts out 4.4V without load. When i add wery small load, the voltage drops. An 3V LED diode will almost not light up at all.
When i meassure the resistance of the black and white wires on the primary side i ger 42ohm. Is that normal?
I get 12.9VAC to the PCB, but only 4.4VDC out. I measure 12.9VAC all the way to the green varistor (look at image under). After varistor i do not get anything.
Some ideas whats wrong here?
that 'varistor' is a MOV connected in parralel with your AC voltage to protect from spikes bigger than 17Vac, in normal condition he is 'open' from the multimeter point of vue.
it's clear you have the correct AC input in that voltage stabiliser, not correct voltage output.
what's fried? maybe some rectifier diode, maybe the ic regulator, maybe something else, without some details we cannot guess what.
trace that AC to DC rectify first by measuring DC voltage on first electrolytic cap, then move forward if the DC is at least 13V
tracing the schematic is simple for your pcb
btw, after what i see on that lab table(the test gear), i'm surprised you ask such simple questions