Yamaha RX-V590 On then Off Problem

[Duranza]

This is some sort of safety feature that kicks in after 3 secs. It started after i had a brown out in my house. If anybody might have an idea of what it can be please share the knowledge. Thanks in advance...

[XEAGLEKEEPER]

Your unit has detected a DC voltage at the output of one of the amplifiers . First you need to check the output transistors in each amplifier channel for damage ie. physical and internal (shorted). Does your unit have a A/B/C/D/E button and a INPUT MODE button on the front panel ? If so, your unit my have a self diagnostic function.

[Leolabs]

Seems that many Yamaha amps at this range suffer from this protection problem.I know there is a thread regarding this kind of situation.

[XEAGLEKEEPER]

Yes I agree. He mentioned that his unit would shut off in 3 sec.
1.)" I "Protect unit shuts off immediately.
2.)"PS"Protect unit shuts off in 1 sec.
3.)"TMP" Protect unit shuts off in 1 sec.
4.) "DC" Protect unit shuts off in 3 sec.


I'm basing this on RX-V630/730 Service manual, Should be close.

[XEAGLEKEEPER]

At least if my HTR-5560 same as RX-V630 craps out it does have a self diagnostic function - by pressing a certain sequence of front panel buttons. I tried it when I first got the unit . Bought it broken on ebay ( unit had been dropped- Required some bodywork-chassis work-frame alignment- and quit a bit of wire&solder&epoxy on a couple small PCB's. After all of that it passed its diagnostic check with flying colors.I was fricking amazed.LOL

[Duranza]

It does have A and B Speaker outputs.. I'll open it and see if i can tell of anything burned.. What should i be looking for? Caps , resistors ??

[docfin]

Service manual for Yamaha RX-V590 available here: http://service-manuals.webs.io

[XEAGLEKEEPER]

Nevermind about the front panel buttons. I looked up your units owners manual and your unit doesn't have a mode input button.So I can't help you with a self diagnostic function.Anyway do you know how to test output transistors? Do you have a DMM (digital multimeter) or analog volt/ohm meter? Yes, remove top cover and give it a good look over for burnt components or obvious problems. Look at the output transistors closely,the output transistors should all be secured to a large finned aluminum heatsink.Look for cracks or discolorations on the transistors . Chances are to determine if the outputs are good or bad they will need to be tested.

[Duranza]

I do have a DMM. I couldn't find any suspecious CAPs and i have gone into test mode but it still shuts off in 3 secs. I will test the transistors, but i'm leaning that the problem might be on something in the power supply overloading. Thanks for the tips. I'll keep at it and report my findings.

[flemdawg]

I'm having the exact problem - shut-off in 3 secs.

The problem's catalyst was a particularly vicious static electricity shock. I got zapped touching the receiver when turning it on.

It hasn't worked since.

I've had the RX-590 since '95, when I bought it new.

Did you come up with a solution?