How to Troubleshoot & Replace Whirlpool AP6017175 / WPW10212598 Valve

Was going to replace the control board and customer support recommended replacement of fill valves (hot and cold). order the parts for about $100 and installed - all works fine now - no control board required. 

Replaced bother the hot and cold water valves on the washing machine. 

REPLACED 

I performed several checks to determine what caused the f20 code from the maintence book that came with the machine. Several possible causes for this code. I checked for clogs, pressure switch, hoses and supply lines. After finding no physical issues I determined that the problem had to be in one of the electrical components, either the switch, computer, or valves themselves. I followed the procedures found in the book using an ohm meter. Everything was within the parameters according to the manufactures specs. Except for the valves. Book said they should have 81 ohms. According to the book if your reading is 10% higher or lower than 81 then the readings are abnormal. I had 1.2k ohms about 15% higher than 81. So I replaced the valves, problem solved. 

Went into top of washer where the solenoid valves were easily accessible. I jiggled the wires and re-checked the units. They performed just fine. I now have spare parts on hand. I'd replaced a valve previously due to leakage, so I like having an extra one handy just in case of a future problem. 

I bought two new valves. They were about 12 years old. They slowly got corroded, I guess, not sealing fully every time letting water in. And when in wash cycle restricted water flow to the point where the washer would error code LF (low flow). 

We replaced the valve and it works again, Yay!!!!! 

Replaced the water valves. 

I replaced both water valves