What I mean is that how can I open the game plastic box or the cabinet to be able to go in the electronic repair on the board. To repair anything I have to open the cabinet or the plastic covers.

Unless you have electronic troubleshooting knowledge the receiver won't be fixable. The receiver has filed replaceable boards meaning, unless you can get a whole new main board it is not fixable. The only thing that might work is to look for a fuse and replace that. fuses come in a bunch of different size and varieties. It would be cheaper to buy a new receiver than to get it repaired.

Hi,

Are you able to advise some more detail for this issue please?
Can you play the game 'blind', which means coin it up, start a game and hear the game making normal gameplay sounds? If so this shows there is an issue with the monitor, or the wiring to the monitor.
Are there any lights lit up on the main game board inside the cabinet? If so this also shows there is an issue with the monitor, or the wiring to the monitor.
Is there any neck glow on the monitor tube, which is the back of the tube itself where it narrows down like a funnel to a narrow glass tube? If so this would indicate the monitor is most likely functioning and could be a game board issue.
You can also determine whether a monitor is functioning by turning up the brightness to full using the brightness potentiometer on the monitor chassis, or the potentiometer on the flyback transformer. The flyback transformer is the plastic looking device that the high tension lead comes out of and connects to the monitor tube, a lot like a spark plug lead connects from the cars distributor cap or coil pack to the spark plugs. It should show a lighter screen and probably with lines in it if the monitor is running.

Sounds like a cold solder joint. Unless you have knowledge of electronics and high voltage, I wouldn't try to fix it myself. A honest TV repairman should be able to fix it. And when I mean high voltage, I mean 2000-3000 volts is average with a CRT TV tube.

This is a bi-amped speaker. That means it has a separate power amplifier driving the bass woofer and treble horn. They have a low-level electronic crossover to separate the frequencies to the appropriate speaker. The electronic crossover is the least likely to fail... so you need to do a test:
You will need to open the unit and using an ohmmeter check if the woofer speaker voice coil is open or has continuity...It should be around 6 to 16 ohms. If it is above that, the speaker itself is blown and will have to be replaced. If the speaker has continuity, then the bass amp has failed and will require repairing by person that is adept at electronic repair. Before opening the unit you MIGHT be able to diagnose whether the speaker itself is blown by seeing if the woofer generates a thump when power is turned on or off. If it does, then likely the speaker is OK and the problem is the amp, otherwise the tests above need to be done. Usually these plastic cabinets are held together with seveal scrwes from the back. Some are in :deep "wells" and will require a very long shaft phillips screwdriver... and they often are long screws that wear one out unscrewing them. A genlte pry after removing the screws will separate the back and the front.

Typically this failure is due to the backlight inverter going out. On this model of tv there were two runs with different parts. Open the back of the tv and open the control box. If you see a large black circuit board on the top, replace that one. If its tan then you need to take out the control box and remove the black plastic backing. If you're looking at the back of the tv the inverter will be on the left side of the control box. Its a long skinny board that has 8 black metal squares on it. Good luck and be careful.

Your problem is most likely a broken cable in your ac cable. Try to replace the cord first (a place like Radio Shack will have replacements). If it's not the cable, then you might have a broken soldering point inside your keyboard. It might be too small of a crack to see, but redoing the soldering points should work.

The DVD rom is probably on its last legs.  Call support and see what they can do for you.  I don't think this is covered under the extended warranties, and it will probably cost you money to fix if its is out of warranty.
Mine did this to me and I am in the middle of trying to repair it myself.  
My suggestion is put it in a enclosed cabinet so that it overheats and redrings so you can send it back.

Hi Tony

Look on ebay or Google for a TO220 heatsink. Believe it or not, the thin metal strip you have referred to, is in fact the manfacturer's attempt at heatsinking the regulator. It is all but useless. There is one here that would be ok.

You will need to bend the veins to squeeze it into the space available. Do this carefully because they can easily break off when you bend them.

Alternatively, consider bolting the regulator to the inside of the cabinet instead. To do this, remove the power board, remove the old regulator completely. Solder flexible PTFE covered link up wire to each pin on the regulator and leave these about 4 inches long, Use heatshrink sleeving or plastic tube to cover all the solder joints, Drill a small hole in the bottom of the cabinet. Use some heatsink paste, a mica insulator on the back of the regulator and bolt it firmly to the inside of the cabinet under the power board. Solder each PTFE lead to the where the pins would have been soldered under the board and then neatly fold the wires under the board before refitting it. I have repaired about 6 of these using this method and I can confirm that the regulator hardly gets warm as the whole cabinet acts as the heatsink. Although it is more difficult to do.
Only attempt any repair or modification if you are confident in your competence in basic practical electronic work.

How old is it?
Open it up and inspect the circuit board carefully for cracks.
TV makers use cheap, one sided circuit boards (meaning weak) that break easily. You are not supposed to drop them.
A cracked board can be repaired.
Of course it could be anything else.
My standard advice applies though:
My experiance is to not put money into a TV that is over ten years old. TVs stress out their electronic components worse than almost any other electronic product. After 10 years, there are so many parts that are ready to fail that your are probably wasting your money trying to get any more life out of it.

Unfortunaley i have a problem with mine also. I contacted Lowrance, and they no longer support or repair this unit.