Red led on Mark 4B : Malfonction or not ?

[domglop78]

Hello
I have a Mark 4B and recently The red LED on the front AV just above the output / level button is weakening. it lights up then from time to time it goes out slowly until almost no more light. if I tap on it it turns on again .... does this come from the diode or from the opto-coupler?
malfonction or not ?
anyone have a schematic with each opto-coupler and the emplacement in PCB with the fonction...

Thank you for your reply and take care of you
dom

 

[GJgo]

Those leads were crimped, super common failure mode. When they go in for service you have have them soldered.

 

[domglop78]

Hello
Thank you for your reply
I am trying to understand ... the diode side connections are crimped? or then PCB side?
i think they is a solder on PCB... same for diode ? no ?
thx a lot...

 

[GJgo]

Sorry, that's the limit of my knowledge on the issue.

 

[rgx612a]

Mine has the same problem. i just tap it and it comes back on. It's not a big deal.

 

[GianBulls23]

mine too but it was never a big deal.
Next time I do the overhaul on Mark IV I will urge the technician to fix it.