Question about Sony KV-20FS12 20" TV

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The set goes into a overvoltage mode

The set goes into a over voltage mode it looks like.I work for a small shop and I don't have a manual yet, i've got one on order. When the customer brought it in she said that the tv and also another one had been hooked up to the same UPS and both went out with in two to three weeks I did not look at the first set. The sony when powered up the LED on the front blinks 3 times, then it shuts down and blinks 4 times as long as it stays powered up. I replaced the STR regulator and I have the same problem. May be someone can give me a heads up on what might be defective. I would think the power supply, the B+ on the horz out collector is 136vdc. Not sure if that's correct.

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A 20In set would probably be around 136v (give or take) while running and would go much higher if it was going into HVS (High Voltage Shutdown) 180v or so. The power supply is working (you have voltage).
Do you have a glow in the neck of the CRT? If not then it may be a bad resistor for the crt heater circuit. Most tubes use the top two pins on the neck socket for the heater, trace them back looking for a resistor, or simply test for voltage at the heater pins (AC), should be low 2-5 volts. If it is shutting down check the Horizontal Output Transistor (HOT) by using an ohm meter (with power disconnected :) ground the black lead and hold the red lead on the center pin of the HOT. Ideally you want an open circuit reading or very high resistance (MOhms), if you have low resistance it means either the HOT or the Flyback Xfmr is bad.
Hope this helps :)

Posted on Mar 11, 2008


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1 Answer

Tv is on an the picture blinks back and forth to black

This is due to over voltage. Not related to supply in overvoltage, but the overvoltage that goes to the main board to this TV. Most TVs works oan a range of 85 to 120VDC. This voltage is generated from the internal power regulator. If the power regulator have any fault, the supplied voltage to the main board may either high or low. In both cases, the main system control IC on board, will detect it and will give you this symptoms.
The work is a skilled one, and only an expereinces service technician can make it right.

Feb 08, 2012 | Sony Televison & Video

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Green power light

This might be due to a problem related to the SMPS (Switched Mode Power Supply) overcurrent / overvoltage dectection circuitry. When an overcurrent or overvoltage condition is noted the SMPS's shutdown circuit will turn the tv off. An over current condition can and most usually is caused by a component overdriving which causes an increase in current requirements for the power supply which in turn causes the shut down of the TV set. In an overvoltage condition a component may not function as well as it should causing a high resistance and this hig resistance causes the voltages level to go up causing the over voltage detector to activate shutting down the TV set.

The best this to do would be to take the set to a shop if you do not have a background in electronics.

I hope this helps,
Thank you,

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1 Answer

CPU overvoltage error"


Did n't you just post in hardware about flashing the BIOS?
Did you enter the BIOS & check the cpu voltage setting to make sure it's correct?
Actually, after the flash you probably should have used the ClearCMOS jumper to reset the BIOS,
then ran thru ALL the settings & manually adjust them for best performance.

Jan 03, 2011 | ASUS P5PE-VM Motherboard

1 Answer

Tv works fine,cut it off and it will not come back on . Red light blinks 6 times, then repeats itself.

this is an indication of a overcurrent/ overvoltage error....meaning short in a voltage supply. I have seen this problem in the shop with this set. IN MY CASE it was shorted convergence chips. but it could also be any of the low voltage supplies 5,10 15,-15 lines

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1 Answer

Kicker protection light won't shut off

Hello newwithtech,

There are 4 possible causes for the amp to go into protection mode. Kicker calls it SORT for Short, Overvoltage, Reverse polarity, and Thermal. If the amp has been in and working properly, it's probably not reverse polarity. And if it goes immediately into protection when power is connected, I'd rule out thermal. So it's probably either a short or overvoltage.

1) Start by removing the speaker wires and see if the amp powers up properly. If it does, one or more of the speakers is shorted or grounded.

2) Test each pair of wires with a multimeter set to the lowest resistance (ohms) scale. Measure across each pair and from each individual wire to ground. Across each pair, the meter should read about 3-4 ohms. From each individual wire to ground, it should read infinity. If the meter reads "0" ohms (shorted) in any test, you have located the problem.

3) If the speaker wires test OK, set the meter to read DC volts and measure the voltage at the amp positive terminal. If the voltage is higher than 16V or lower than 9V, you've located the problem.

4) If the voltage is OK, remove the RCA inputs and test for proper power up. If it powers up without going into protection, you have a shorted/grounded input. Replace them one at a time to determine which one(s) is/are defective and replace the cable.

If these tests show all the wiring is good and the voltage is OK, the amp is probably shorted internally (most likely an output MOSFET), and requires service at the component level. You need to take it to your local audio shop or send it to Kicker for repair.

Hope this helps.

Jun 29, 2009 | Kicker KX300.4 Car Audio Amplifier

1 Answer


A vehicle alternator control device in which, when a signal detection portion detects a determined input signal, an operating mode of an overvoltage warning portion is switched to a detection operating mode by an overvoltage warning operating mode switching portion. In the detection operating mode, the overvoltage warning portion is activated when a voltage below a determined voltage has continued for a time that is less than a determined time. Accordingly, checks related to the operation of the overvoltage warning portion can be completed in a short time at a plant or the like.

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Mar 01, 2009 | 1997 Mercury Villager

1 Answer

Gigabyte GA - x48 - DS4.

Hi Plineh,
It sounds like a bios issue. (So it would be considered a hardware issue).
Uninstall all driver software for the radeon. (If the software for the nVidia software is in the system, uninstall it as well). Check your bios settings, see page 51 in your manual.
Set, Robust Graphics Booster, to [Auto].
CPU/PCIEX Clock Driving Control [800mV] you may need to go lower.
CPU Clock Skew Control [Normal]
(G)MCH Clock Skew Control [Normal]
System Voltage Control [Auto]
DDR2 OverVoltage Control [Normal]
PCI-E OverVoltage Control [Normal]
FSB OverVoltage Control [Normal]
(G)MCH OverVoltage Control [Normal]
Loadline Calibration [Auto]
CPU Voltage Control [Normal]

(Restart the system with one radeon installed into PCIE_16_1 slot.) Once windows finishes loading re-install the latest software for the radeon. (Download from here):
Monitor the card & see if it goes into hyperdrive. If it does not than sut down the system & add the second card into PCIE_16_2 & run in crossfire mode.
You may need to adjust the bios setting further if either card goes into hyperdrive. Your board was made in 2008 & is still under warranty. I call to the manufacture's tech support is something I would not exclude.

Good luck & take your time!

Nov 04, 2008 | Intel Motherboard

1 Answer

Hello, I have a pyramid power supply(PS-52KX), that recently started with a overvoltage problem. I run a Galaxy DX94 HP 10 meter transceiver, and just recently, when I key up the radio, the...

I'm not sure what you mean by 'wide open voltage'. If it's over 17v, the supply may have multiple problems. I don't have the 52kx schematic but other Pyramid supplies have over-voltage protection. There is an SCR that is triggered when the voltage gets to ~17v. This should clamp the output and trigger a shutdown. You should check the 16v Zener diode and the SCR. If the SCR or the Zener is defective, that would prevent the over-voltage from clamping the voltage. Also confirm that the SCR has a solid connection to the ground terminal of the supply. If it's open, that could prevent the clamp from shutting down the supply.

If the voltage is going high, measure the DC voltage from pin 4 to pin 5 of the LM723. It should remain the same at all times. Also measure the voltage from pin 5 to the ground terminal of the supply. That should also remain constant at all times.

Aug 20, 2008 | Pyramid - PS21KX 20 Amp Power Supply Car...

1 Answer

No power to tv

Hello Olsol,


This is an indication of a problem in the power supply. This problem can be in the switching power supply or in the high voltage power supply in either case there is some overcurrent or overvoltage condition which is cuasing the issue. Look for blown fuses and replace them, once this is done power on the set. If this works then great, but if not look at what is happening prior to the fuse blowing. Then using the schematic and a voltmeter attempt to find the shorted or open components by the lack of proper voltage readings. However if you do not have a background in electronics, I would suggest that call a TV repair shop and have this TV repaired.


I hope this helps,

Thank you,


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