My top drawer says it isnt getting any water and the water hose is rattling. the bottom drawer works fine

At some point the two drawers individual drain hoses are joined using a "Y' type connector. Check this, and everything beyond this point for restrictions or blockage. It sounds like the bottom drawer is pumping its drain water out normally, but some of that water is backing up to the upper drawer. This is an installation or plumbing problem that is external of the dishdrawers.

Try to reset your dish washer. Turn off main power supply and leave it for at least 1 min. Is there any error code appear/beeping sound?

It is the drain water from bottom drawer that is finding its way to the top drawer. This could be due to incorrect drain hose height. Check in installation manual. Alternatively you will have to buy an air gap kit and connect the two drain hoses separately to the kitchen sink.

http://www.genuineapplianceparts.net/ecart/item.php?item_id=250&category_id=58

As the drawers share a common outlet to the kitchen sink drain, it is the drain water from bottom drawer going to top drawer. Can happen if the drain hoses are not following the correct specifications for installation. An air gap kit is available to solve the problems.

Refer
http://www.genuineapplianceparts.net/product/WT50/WT50-Dual-Air-Gap-Kit/?preadd=action&key=WT50

If your bottom drawer works fine then your inlet water valve below the bottom drawer is bad. Click on the link below to see how to repair this dishwasher.

Appliance Repair Video

Try to isolate the drain hose of the top drawer by disconnecting from the U hose. Run the bottom drawer.

Similarly isolate bottom drawer and then run top drawer.

See if problem is linked to back flow from drain.

I am assuming by now you may have already solved the problem.

check the check valve on bottom drawer. unplug hose drain hose off drawer underneath. a small ruber check valve can be clogged. if its good replace it

yes there is. It is just inside the white hoses that drain the system. 1 per drawer. They cost about $0.50 but are a real pain to get to. This flap will go bad in about 3-5 years and maybe sooner depending on the temp of the water used.

If the bottom flap goes bad, using the top drawer will drain into the bottom drawer.

We just had the same problem. We took off the three screw on the back to remove the top panel on washer. From there we took the screws off the electric face plate on the front. Be careful, there is a screw located inside the door. You must open the door to get to the screw. Next we removed the bottom panel door and then the four screws to the mail metal panel on the front. Hold that panel because the rubber gasket is still connected. Then you will see a rubber hose directly under the drawer. Take the rubber hose off at the bottom nearest the drum. We found a sock that had wedged itself up and was causing a back up. After I cleared it, the washer works just fine.

Could be the little non return valve mounted underneath the top drawer. Lie down on the floor under the top drawer, remove the main plastic pannel covering the bottom to expose the black drainage hose (you may need to cut away a cable tie). Remove the drainage hose from bottom of the drawer - at the start of the drainage hose there will be a small rubber type flap - if it looks broken or worn out, it will need replacing - call F & P for a replacement, approx $5 + postage for a pair (one for the top drawer and one for the bottom)
Hope this helps