Hi. I'm Smitty. I am a professional appliance repair consultant here to help you diagnose, and repair, your appliance.
You are on the right track there. Disconnect the water line from the outgoing side of the water inlet valve (push in on white ring and pull out the line). Have someone actuate the dispenser switch and see if you get the same amount. If you do then the water inlet valve is the problem. replace it and you are good to go. These are common parts and are available from your local appliance parts retailers and some models are available at Home Depot, and Lowes. Sears also carries replacement valves.
If the flow is greater than at the dispenser look for partially frozen lines or kinked lines at the bottom left hinge of the freezer door. This is where the line goes into the door from the back of the unit.
Please let me know if you have any other immediate concerns.If not please select a positive rating at this time. Doing so will not close your question, and after you rate my service you may ask any followup questions you like. All at no additional charge.Thank you for the opportunity to serve you. Best, Smitty**How to rate your expert**
Answer man was correct: bad water intake valve. Thanks!!!
You are mosrt welcome. =)
Actually "Answer Man" is a different expert but Im sure everyone understands.
Thank you for the update. Im glad I could help.