F.P. Double drawer. When I use the bottom drawer, it pumps water into the top drawer.

SOURCE: no power top drawer

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?

SOURCE: fisher paykel

Check your email

SOURCE: water in top drawer

I am not a repairman but have installed several duel drawer dishwashers. Most dishwashers have a check valve preventing backflow. Water under pressure will always follow the path of least resistance and in your case it is going into the upper drawer. Be sure the drain is open and flowing easily under your sink whether that be the disposal or a TEE. It may help if the drain line is elevated as high as it can go under the sink just before it reaches the drain. How often do you use the top drawer? Perhaps run a cycle on the hottest cycle without dishes to attemt to clean or force through any contaminants in the check valve through into the drain. Hope this helps, Ken

SOURCE: I have a Fisher Paykel dishwasher with water in top drawer

You need a Air gap kit designed by Fisher and Paykel to address this problem. It is pricey but it is worthy. I used this and very happy with it since no back flow problem from one while other running. Here is a link to order it.http://www.fisherpaykelparts.net/product/WT50/WT50-Dual-Air-Gap-Kit/

SOURCE: I have a fisher & paykel dd603 double dish

Fisher Paykel dishwasher repair video, this video will walk you through repairing your dishwasher.
http://www.appliancerepairlesson.com