I've got a Harman Kardon AVR-635 receiver that I've had for about 2 years now. Two nights ago I was watching TV and the power just cut off out of no where. It felt quite warm, but not extremely hot and I thought maybe the dog stepped on the power button on the control so I turned it back on. It seemed to run fine for the next hour or so until I turned it off.
The next day my girlfriend noticed it turning off 2 more times only to try to turn it back on and it cut off immediately. So, last night I had it on for about 30 minutes and it cut off. When trying to turn it back on it would cut off immediately. However, if I pick up the receiver and lightly jar it on the shelf it sits on it will turn right back on and work for random periods of time afterwards. I tried it three times and the first time it worked for about 45 minutes, the second time about 10 minutes, and the third for about 25 minutes.
During the times when the unit cuts off it is only slightly warm and the sides of the case are slighty higher than room temperature. I've checked to make sure there's a solid speaker connection and I plan on disconnecting it tonight, opening it up, and cleaning it out. Do you guys have any other ideas?
If you do, check your speaker wire to insure that the + an - are not in contact.
If not, visually check the wire, especially at the point of connection to the amp and to the speaker to make sure the ends are not crossing over to the other binding post.
Cleaning might solve the issue for you too.
I suspect others on this forum will follow with additional suggestions.
To check for continuity in a cable you'll have to disconnect the cable at both ends. Set your meter to "continuity check" function or "diode check". Touch one probe of your meter to one of the bare conductors at one end and the other probe of your meter to the other bare conductor at the same end of cable. If the meter reads continuity, you have a problem with the cable. Unfortunately, having moved the cable, any small cracks in the insualtion could now be rectified and a bad cable might not read as such but perform as such when placed back into the system.
I would be more suspicious of a cold solder joint inside the receiver. This is not totally out of the question in modern components. Since such problems are also difficult to diagnose after the component has been moved, this is something for a tecnician to resolve.
well....I just went home for lunch and the receiver had been off all night since 12pm and I tried to turn it on it clicked on and then back off. I shook it a bit and it came on and ran for about 20 minutes until I left. I disconnected the speakers and left it on. We'll see what happpens when I get home in a few hours. Thanks for your suggestions.