Pioneer N-50 power blue led blinking,unit is not booting up

Same Issue

Wow, I can't believe I found this thread and it was just replied to back in February.

I too have the exact same issue with my Pioneer N-50. The unit seems well built and looks attractive so I would hate to throw it out.

Seems like it's stuck in Standby.

The blue LED is blinking on the power button after it's depressed. But if I unplug the unit while it's blinking and wait a few seconds, and then plug it back in, the little red "standby" light lights up and the blue LED on the power button is no longer blinking.

Any ideas or suggestions?
 
Same Exact Problem

Hey,

I've the same unit and the same exact problem, flip the on button and the blue "on" light just goes off and on, indefinitely (I left it on all night once just to see how long it would continue - it went all night.) Never powers up, just gives the blinking blue light. It HAS been a decent unit, and this just seems almost like it's trying to tell me something - however, there's nothing I can find in the manual, including "troubleshooting" that mentions this as a problem, much less provides a solution. Anybody know anything about this?
 
Do you get around 380V DC across C203? CAREFUL!! Lethal Voltage!!! This is the starting point.... the standby voltage is derived from here.
R251 and R252 okay? ... i.e. NOT open circuit?
R220 okay? (NOT open)? How about R231 and R232??
R229 should be 10ohms (NOT open circuit)
ZD202 should have around 5V on it. This is your +5V for the whole unit. This Zener runs HOT.... and it is possible that a cold solder joint has developed around its eyelets. Look for the signs of burns on PCB. Without this +5V, your unit will never come ON.

Q201 closes the relay RLY201 when you turn the power ON.... and then you get your other voltages from the power transformer (linear power supply for +12V and a secondary +5DC rail.... see NOTE right below). This is what SHOULD happen when everything is okay. NOTE: there's another +5V, derived from a fricken Zener ZD251 (?) ... anyway... check the Zener and the surrounding PCB area for discolouration/signs of excessive heat dissipation. This is applicable only once the unit turns ON (it comes for a transformer)

So, check the above first (in bold).

..... the switching IC might be faulty..... IC201... or its Zener reference voltage (ZD210 and Z203 connected in series...) might be incorrect / not present.
 
Last edited: