I have a Whirlpool Duet front-loading washer. Sometimes it stops and won't spin then displays code F02. Usually turning it off for an hour and restarting solves the problem but not tonight. When I try to restart it, it makes a grumbling sound for a while then gives up and beeps/displays the code. Previously I opened it up and there were no obvious problems. I checked the drain pump trap and there was nothing in it. There isn't much in it so I don't think overloading is the problem.
The pump is bad or you use too much soap. Run a load without soap. If a load of clean clothes makes suds in the washer, you definitely use too much soap.
The pump can't pump suds -shopyourway.com
Of course it could be a senor malfunctioning somewhere...