Kitchen Large Electric Appliances - GE Fridge again

I have a GSS25KGMD BB. Over the last nine months my frezzer coil continues to freeze over. I have replaced the coil fan which was bad and the control board, which holds the defrost timer, both fixed it at the time. It is iced up again what else could it be?

I have a GSS25KGMD BB. Over the last nine months my frezzer coil continues to freeze over. I have replaced the coil fan which was bad and the control board, which holds the defrost timer, both fixed it at the time. It is iced up again what else could it be?

Check to see if the drain tube is clear. I have ran across some that were blocked and when the defrost cycle kicked in the water was not able to fully drain. This left water sitting around the drain, which would freeze and cause a ice dam. Each defrost cycle caused the dam to get larger.

If the drain is clear, ensure the freezer is sitting level and not hindering the draining of water down the tube.

Checked the drain tube and it is clear.
I have also checked continuity of defrost element and it is OK
The damper and motor between the fridge and freezer appears to be working as well.
Is there a way to check the defrost timer on a circuit board with out high tech equipment? I am think of trying to send the new circuit board back for another one.

Thanks for all the help.

Wish I could help you out on that one. I haven't worked on refrigerators in a number of years and things have changed, as with everything. I don't believe there is a easy method to check the defrost timer on the circuit card, it is probally an IC chip now. Even if the chip is good, there may be a problem with the run leaving it or possibly a bad input to it. Like you said, without a circuit card tester set up for that particular board, it is almost impossible to verify all the inputs and outputs are good.
Having said that, if you have checked everything else in the circuit (including wiring and connections) and the board is the only thing left, run with it. It would be nice if the manufacture of the board has some sort of warrenty on the board, so you don't have to pay for another one.
I would suggest contacting a local repairman to see if they have a tester, but I doubt it. The cost of the equipment verse the use of the equipment, usually doesn't justify the purchase.
Anyhow, let us know how it goes. Hopefully, all will work out for you.

Thanks for all your help. You guys have been tremednous. I hope the card is the trick.