Hello, this is my first time in this forum please bare with me.
i am a student on a research project that will use the HP4145B. sadly the equipment is borked. just by plugging the power cable the equipment tripped our MCB. i have searched around to find the service manual, but only found the one for HP4145A. i have heard that it is more or less the same, just different drive? cmiiw (
https://archive.org/details/HP4145ASemiconductorParameterAnalyzerOperationAndServiceManual)
the professor gave us the green light to diagnose it. so i proceeded to tear down the equipment and extract the A11 module based on the troubleshooting tree below.



i did the isolation check, but the short still existed (i left it measuring the resistance in the multimeter for a minute hoping any capacitor would be charged enough to show any resistance, still shorted), so i didn't plug it in.so i desoldered the fan to fully pull this module out, turns out there is a capacitor got blown to bits.



here is the schematic for this part

i first assumed that cap is fully shorted, the source of the problem, but the multimeter shows 0.4kohms(while the power button is off), while the c14 socket shows around 0 ohms, if the power button is toggled, it shows 0 ohms

based on that, and the schematic, i determined that the EMI Filter might be shorted as well.
soo thats the entire diagnosis journey, is my conclusion correct? or i missed some crucial steps?