Model no.LA22A450C1 5.VOLTAGE absent - Samsung LA22A450 22 in. LCD TV

no not t-con its the led's or the led power on the power board faild. cpi;d even be the switching voltage control chip on the power board. or the voltage regulator chip on the power board.

Check and replace damaged component/s at its horizontal scan output section circuit. Check the LOT (Line Output Transformer) too for damage. Replace the horizontal scan output transistor. Check the input voltage to LOT. If the voltage is absent check the feeder resistor; if any. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts.
http://electronicshelponline.blogspot.com/

Replace damaged component/s at its horizontal scan output section circuit. Check the LOT (Line Output Transformer) too for damage. Replace the horizontal scan output transistor. Check the input voltage to LOT. If the voltage is absent check the feeder resistor; if any. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts.
http://electronicshelponline.blogspot.com/

Check the LOT (Line Output Transformer) too for damage. Replace the horizontal scan output transistor. Check the input voltage to LOT. If the voltage is absent check the feeder resistor; if any. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts.
http://electronicshelponline.blogspot.com/

you must check an open resistance( bad resistor ) coming from the power supply section going to the horizontal drive transistor collector pin.

Possible that the battery is bad or weak, the adaptor is not outputing the required voltage or is faulty or that the charging circuit is faulty in the motherboard.
In all these you need to check on the voltage incident on the battery terminals. So connect the adaptor an check the voltage at the battery terminals in the laptop, if absent check at the pins, if absent check on the adaptor circuit.
check this link;

http://www.fixya.com/support/r5164850-laptop_power_supply

If voltage is present then the battery is a suspect, if not the motherboard charging circuit has problems if adaptor is good and there is no charging.

Check the voltage on the adapter and is absent or low the adapter is faulty. If not check the voltage on the battery terminals in the camera. If absent there can be a break or poor connection . If there is good coltage then the battery can be faulty. It is ideal to swap the battery and take a test before you buy a new one as a confirmation can save if there are another other issues.

The voltage at the HT coil is important and the FIRING TRIGGER to the HT is also most important. Now remove the spark plug and crank the engine while check for HT spark on the plug. If absent check the voltage at coil, if absent check the main switch ./ fuse which can be faulty.
IF the coil has voltage but there is no switching then the ignition circuit must be checked.

This is purely a fault in the display unit. you need to check the power supply to the display unit. Check the filament voltage and the grid voltage to the display from the display driver processor.
If absent the power supply should be checked , it can be a open fusible resistor if voltage is absent. If not the IC is defective. Check for dry joints of the display unit, the IC or the connector to the display board.

Possible fault in the tone ringer IC. This is normally triggered by the incoming signal before the line is switched on. So the IC takes the pulse straight from the incoming voltage , normally from the line in rectifier.
So use a meter to see with a test call for the pulsating voltage on the IC, if present then the IC is faulty. If absent check the inline signal being absent to this section.