Loss of vertical sweep - Panasonic TC-21PM10RQ 21" TV

Loss of vertical sweep or deflection.

2,4 is one of 5 error codes and means:

2blink-then 4 blink---------vertical circuit problem

The set may have a loss of sweep or even Glycol may have leaked from the picture tube above it onto the board in that area.

Vertical circuit is on middle board at front right edge.

in the model listed the set will "turn off" the tubes if No High Voltage, a vertical or horizontal circuit loss of sweep etc.

Need a schematic and a meter to start checking things.

Hello
It may be due to an Integrated Circuit [IC] fault. Your TV has lost its vertical sweep, and the is why you see a norizontal bright line across the center of the screen. All TVs has bot Hotizontal and Vertical Sweep to spread picture on the screen. When Vertical sweep fails, you will see a horizontal line, and when horizontal sweep fails you will see a vertical line at the middle of the screen.
n your TV, most likley the vertical Ic is faulty. This is a common phenomena in almopst all telivisions. The said IC is diretly soldered into the circuit board inside your TV. To replace it you have to open your TV. Take all precautions before opening the back cover of your TV. You are going to work with an electrical equipment, and keep it in mind always. After opening the back cover, just locate where the Vertical Output Ic is. It will be normally screwed to a heatsink plate, inorder to radiate heat from it while working. You can locate it by the following method. Different TV circuits has different positions to this Ic. Just look on the Deflection Yoke [the coil fitted on the neck of picture tube]. From there four wires will go to the main printed circuit board. Out of which two of them will be thick, and other two will be thin. The two thin wires are the carriers of vertical sweep from main board to deflection yoke. Follow the the two thin wires. You will see it to be pluged into one point at the printed circuit board. Just upside down the printed circuit board, after pulling it outwards, not disturbing any of the wirings, and look through the circuit track, to which point the tracks goes to. Somewhere near to it you can locate the above said IC.
Just take the main input votage to that IC. It will be normally 18v to 35VDC. You must have multimeter to measure this voltage. If the voltage is there, look for any loose solderings over there to the legs of that IC. If there is any soldering loose, the IC will not work properly, and vertical sweep loss will be the result. If there is proper voltage check the voltage at the output pin of that Ic. It should be almost half the voltage of the supply voltage. If it is not there, make sure that the IC has damaged.
Resolder it out from the board, and go for a same type and number. Replacing it will solve the problem. Normally vertical output ICs are not very cosltly. Here in India, all types of vertical Ics will have a price rate between 80 to150 Indian rupees, that is upto four American Dollars. Ok.

follow the 2 sets of wires off the yoke. one goes to the horizontal sweep section and the other goes to the vertical. the drive ic with the metal tab is blown.that is what drives the vertical deflection. there is a few capacitors there. 1mf at 160v and .47 at 160 and 2.2mf at 50v on most sylvania sets . if the plastic on the top of the capacitor is shrunk,it is getting hot and is no good.that can cause a loss of sweep or foldover.99% of the time it is the vertical output ic that is gone.

Hello,

Most probably the vertical deflection amplifier is failing. The most common part that fails is the vertical output transistor.
The set is too old to find documentation on part numbers and descriptions. Probably the part is no longer available and you will need the assistance of someone who can help you find an equivalent transistor that will do the job.
Of course, without testing we cannot be certain the failure is the output transistor. It could be from something else such as the voltage regulator that feeds the dc line to the vertical section. Could be the vertical synchronous level that goes too low to trigger the vertical sweep generator.

Other bad parts in vertical deflection circuit though there are not that many parts that would kill the deflection entirely.

Loss of power to vertical deflection circuits. Check for blown fusable resistors/fuses and bad connections.

Loss of vertical oscillator or vertical drive signals
Good luck.

most common vertical ic s are7840 or 78040...but ur problem is 100mfd 40v capacitor in vertical section.. change it then u will get perfect pic...have anice day..

It has been my experience with that model mitsubishi that the usual culprit is loss of vertical sweep. If the beams in the picture tubes stops moving up and down this is detected by the micro processor and the video is blanked, but the set is not shut down. The usual cause of loss of vertical sweep is bad solder connections on the deflection yokes or a failed vertical output IC.

There is no such thing as a "vertical sweep circuit board" in that set. The vertical circuit is part of the sweep module. And BTW that type of symptom is more often a power supply filtering problem anyway.

you have loss of vertical sweep, need to know what type of tv it is.