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[quote="krex"]I have a Zenith model # XBS444 Receiver/DVD Player/ VCR that shuts down after about 5 minutes of any opperation. It seems as the unit is overheating and the fans do not turn on -ever. I have tested them now on 5 different days but they are not receiving power at the plugs on the board. What can be replaced to tell the fans to turn on and should that also fix the shut-down problem?[/quote]
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Posted: Fri Jul 23, 2010 1:20 pm
Post subject: zenith xbs444 overheating
info for anyone who owns a zenith xbs444 dvd/vcr/tuner combo,, and the unit shuts off after a short period,, due to the voltage regulators overheating,,,i have found an alternative fix without having to replace the regulators,,,being that the problem is they are sensitive and affected very quickly by the heat,,,airflow is essensial,,, step 1: remove the fan,, then connect the black wire to a closeby point on the frame,, a good spot would be the brace screw for the circuit board nearby,, this will keep the fan running at all times,,,step 2: use some tape to cover the open holes on the bottom frame panel, and then cover at least 75 percent of the larger vents on the right rear side of the cover,,,step 3: make sure the cover is replaced nice and tight all around,,this will create a larger airflow through the vents for the regulators,,,i have done this , and it works,,,not a problem since!!
Posted: Sat Jun 05, 2010 1:10 am
Let's hope theirs still need repairing after all this time.
Posted: Fri Jun 04, 2010 4:19 pm
Post subject: Failing XBS444
Replace the voltage regulators on the audio output board. They are NTIS designated 7805, 7809, 7812. The last two numbers designate the regulated voltage. The most probable culprit are the 5 volt units.
IC 705, 706, 707 are 5 volt (7805). IC702 is 9 volt(7809) IC 703 is 12 volt(7812).
About a buck apiece
Posted: Mon Nov 26, 2007 8:03 pm
Post subject: any luck fixing this?
I'm having the same problem, I've traced the 12v circuit and it looks good, but the C (common?) seems to be opeen, or at least I can't find where it is going. Have you had any luck fixing yours? I can be reached at
Posted: Tue Apr 10, 2007 9:49 pm
Post subject: Zenith home theatre shuts down
I have a Zenith model # XBS444 Receiver/DVD Player/ VCR that shuts down after about 5 minutes of any opperation. It seems as the unit is overheating and the fans do not turn on -ever. I have tested them now on 5 different days but they are not receiving power at the plugs on the board.
What can be replaced to tell the fans to turn on and should that also fix the shut-down problem?
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