Shuts down mine does the shut down after a couple seconds, I did replace two 1 ohm resistors that were bad, you say check the capacitors? any advice on how? also it did have the humming noise the last time it actually powered up. thanks for any help. Jesse

Previously it had turned off while watching a program, however now it cuts off as soon as I turn it on. This must be over-current protection.How to check: (0)download TX-NR636 service manual which doesn't teach you how to fix over-current protection.See P.11(1)Press display and at the same time Press ON/STANDBY TWICE(2)press home(3) I (over-current)-- 25(temperature in my amp)--42(volume level in my amp)--OA(listening mode in my amp)shown.()shown may be different in your amp. For me: -___25___42___OA. In normal condition, NO WORD in left giving you this "-"__25 instead of alphabet.How to fix over-current protect.Symptoms:time taken to shut down.3 seconds (DC protect) OR immediately shut down (Over Current protect) If over-current protect do thefollowing steps(O)unplug the amp.(1)download NR636service manual.(2)open the amp metal cover.(3)measure 7 large white resistors resistance loacated next to power transistors mounted on a large heat sink with black probe touching the middle pin and red probe to first/left or third/right pin.(4)If this 3 Pins large white colour 0.22ohm x 2 resistor is open with infinity ohms ,(5)replace it and jot down this channel for example left surround faulty. Usually only 1 channel went faulty.(5a)When the white resistor didn't burn, "2 channels" were damaged due to bad soldering joint of the large white resistor, however. (5b)When this happened, time taken of shut-down due to over-current is 3 seconds NOT immediately.(6)the two large power transistors next to this white resistor 0.22 ohms x2 should also be replaced.(7)plug the amp(8)switch it on(9)if ok, troubleshooting get done(10)if not ok(11)replace ALL the components of this power amp channel except these in 11a.(11a)P.30 use left channel as an example. R6140,R6150,C6050,R6160,Q6070,R6430,L6000,R6170,R6180,D6000.(12)pre-amp section no need to check.remember if not OK, the replaced 0.22ohm x 2 resistor and 2 power transistors maybe shorted again. Check them first. If OK, replace ALL Components in this channel except 0.22 ohm x 2 and 2 transistors. 0.22 ohm x 2 means left and middle pin 0.22 ohm as well as right and middle pin also 0.22 ohm that are 2 pieces of resistors with 0.22 ohm in a large white 3 pins resistor.Remember sometimes the0.22 ohm white resistor is normal. If so, use a digital multimeter to measure the be bias transistor voltage via multimeter diode test function. You can compare the normal value,580mV to 650mV with faulty one,3.2mV. And the CE resistance is 1.8ohms only instead of 3 Mega ohms.

Yes, I have a clue. Most likely it is a bad solder joint near a chip. Could be at a supporting device like a resistor or capacitor. It heats up and looses contact. Replace it if is a cheap or factory radio.

tThe diagnostic circuits is shutting your TV down. In most cases the set will shut it down immediately. Apparently your set hasn't shut completely down yet. When you turn your TV on the diagnostic circuits send a low voltage, low frequency signal through all the circuits and depending on how they come back whether the sets powers up to full power. If a problem is detected it will shut down to protect the other circuits. It sounds like you might have some capacitors going bad on your power board. A capacitor that is going bad would let it come on for a few seconds then the diagnostic circuits would see the capacitor getting further out of tolerance and shut the set down. If you are a DYS type person you might want to lay it flat of it;s face and remove the back. A bad capacitor will be bulged out on the top. are Replace capacitors with the exact uf value and if you can go above the rated voltage but never below., If this isn't the problem then it is probably the main board (the board where your cable hooks up to), There are other things that cab causes for this but I would check the capacitors first.
Col. Dana Gillespie

This is a 2 channel stereo unit. Ebay shows @ a dozen of them for sale between $46- $90. In davenport Iowa, which isn't an expensive area, you can't touch a repair for that. Check your area Our estimate fee alone is $43

open and blow clean the insides and try. had worked for me.

I think this might be bad/swollen capacitors in your power supply, or something odd in the +5VDC circuits of the power supply, but I am posting all of the things I have found so far with these TVs.

Here are few possible solutions:
If you have no red light and you have a Megmeet MLT386 power supply, check these parts:
1) Swollen caps on the PS secondary circuit (may cause the red light blink or shutdown problems).
2) Blown fuse F1 (5A/250V) this is caused by a shorted FET at QA1 (20N60), you may also find that SMT cap CX23 is burned up (.001uf) which is in parallel with diode DA2 which may be damaged/shorted, replace these components.
If the power LED goes from red to green when powered up but no picture, then it might be lost +24VDC from the power supply:
3)Check fuse F2 (3.15A/250V, I put a 5A in), if it is blown, replace FET at QA2A (9N50C), replace QA2 as well (9N50C). Check SMT resistors at R233,R234,R235,R236 (.47 ohm). If open, replace with .1 ohm 1W or 2W resistor (easier to source). Also replace SMT transistor QF1 (2X4 or 2N4401 NPN transistor). And replace diodes at DS2 and DS1 (HER207), DS2 was shorted, DS1 was ok but I replaced it anyway.

I dont know as much about the Megmeet MLT169A, but it has similar problems and similar components.
4) I had to replace all of the capacitors in the secondary circuit (there are six in a 3x3 row marked EC9 (1000uf35V),EC10(1000uf35V),EC14(470uf35V) and EC18,EC19,EC20 (all 1000uf35V).

OK for the Megmeet MLT169A with red flashing LED when turned on we found that IC7 was bad. This is an SMT component on the solder side of the power supply. It is a 4407P (P channel 30V MOSFET). For testing purposes, we jumped across it to feed +5V to the TV permenently instead of allowing +5V to go into standby.

Sounds like you soldered two of the convergence pins together by accident. If its shorted the TV will shut down.

First, check which type of protect first.

Symptoms:
3 seconds (DC protect) OR immediately shut down (Over Current protect)

How to confirm?
1.Unplug the amp.
2.Remove the metal cover.
3.You will see a long vertically installed pre-amp board mounted next to those large power transistors fixed by 12 screws on a large aluminium heat sink.
4.Remove this long vertically installed board mounted by 2 screws.
5.With 2 screws removed, just pulling this board out and hold it with one hand.
6.Plug the amp and switch it on.
7.If your amp stays ON forever, the problem is from this long board.
8.If switch off at once, the problem is from power amp board.
Try the above- mentioned steps. If DC protect, write an email to me via searching you tube SR600 capacitor replacement. Don't be afraid.
So many people wrote to me.

If over-current protect do the
following steps
(O)unplug the amp.
(1)download DS-TX494 service manual.
(2)open the amp metal cover.
(3)measure 7 large white resistors resistance loacated next to power transistors mounted on a large heat sink with black probe touching the middle pin and red probe to first/left or third/right pin.
(4)If this 3 Pins large white colour 0.22ohm x 2 resistor is open with infinity ohms ,
(5)replace it and jot down this channel for example left surround faulty. Usually only 1 channel went faulty.
(5a)When the white resistor didn't burn, "2 channels" were damaged due to bad soldering joint of the large white resistor, however.
(5b)When this happened, time taken of shut-down due to over-current is 3 seconds NOT immediately.
(6)the two large power transistors next to this white resistor 0.22 ohms x2 should also be replaced.
(7)plug the amp
(8)switch it on
(9)if ok, troubleshooting get done
(10)if not ok
(11)replace ALL the components of this power amp channel.
(12)pre-amp section no need to check.
remember if not OK, the replaced 0.22ohm x 2 resistor and 2 power transistors maybe shorted again. Check them first. If OK, replace ALL Components in this channel except 0.22 ohm x 2 and 2 transistors. 0.22 ohm x 2 means left and middle pin 0.22 ohm as well as right and middle pin also 0.22 ohm that are 2 pieces of resistors with 0.22 ohm in a large white 3 pins resistor.
Remember sometimes the
0.22 ohm white resistor is normal. If so, use a digital multimeter to measure the be bias transistor voltage via multimeter diode test function. You can compare the normal value,580mV to 650mV with faulty one,3.2mV. And the CE resistance is 1.8ohms only instead of 3 Mega ohms.

did u cheak the input cables does it do it on dvd input as well as others ?

There is a resistor on the CRT board that goes bad sometimes. I cannot remember the number but it is a common fault as the TV starts up and then detects too much beam current and shuts back down. If you have a multimeter, you can check the resistors if you know how the color coding works on these resistors. If you do not, take the set to a repair shop, as this problem, if this is the problem, should not cost that much to replace a 10 cent resistor. Good Luck