I have a Samsung LNT4042H which is constantly flashing I have been told to cut the Jumper J852 or 854 but they don't exist. Which jumper do I cut to correct this problem

cutting a jumper will not fix this. the TV needs proper troubleshooting to determine if the issue is power or with the digital board.

Just cut all the jumpers; one after another.

Cut off all the jumpers.

These blinks [flashes] are fault indication (Error Codes). From the number of blinks occur at one time switch ON, you can get an idea about the faulty circuit section inside it. This will make repair easy. These are called blinking codes. Make sure about the exact number of blinking of the standby/power LED, by switching On & OFF the set, for at least two times. Count it carefully. If you wish to get some details, check the site linked here. It has details about blinking codes, and fault locating procedure, to many popular brand TVs and other devices. http://electronicshelponline.blogspot.com/
Blinking codes details to many popular brand TVs are given. Surf the site with patience.

There is no jumper on this model of power supply to cut. Although you can send your power supply here http://www.electronresort.com/repair-service-c-144/samsung-bn4400260b-power-supply-inverter-repair-service-p-5297.html to have it repaired if you can not find one.

Pull the back off the tv. Look at the power supply. Find jumper designated JP854 on power supply. Take a pair of wire snips and cut that jumper out of the circuit. Put the tv back together. That's it.

You might want to call Samsung with the model number as I remember seeing a notice for certain models that have this issue---a jumper plug needs in those sets to be removed that is located on the power board.

Here is the jumper settings for Samsung hard drives. Assuming that your hard drive is bigger than 32GB you have to use the "General Pin Setting"

Note that after changing the jumper, it's suggested to partition and format your hard disk drive.

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Some of the thermostats from Honeywell require a jumper wire on the thermostat between the RC and the RH connection for the heating to operate. It is possible that your installation needs this jumper wire installed for the heating to work.Verify that this jumper wire is installed if your thermostat requires it. If it requires the jumper wire and you do not have one you can cut a small piece of existing wire on the connections to make a jumper wire. There are also some thermostats with a jumper switch for electric heat and gas heat...make sure that it is on the proper setting.

Hi,
to make a HDD as slave, put off the jumper out.

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