Thanks for your fast reply Don. I thought by pressing the close button down continuously, that that basically bypassed the sensors. I will definitely run those checks on the sensors tomorrow after I get home from work.
Thanks again!

Well, I checked the sensors and they seem to be lined up and mounted firm. Both lights are on solid with no flicker.
I checked voltage between terminals 2 and 3 and got 5.9 vdc.
I'm not sure what to look at next. Any other thoughts?
Thanks again.
Mike

What puzzles me is you say you get 5 blinking lights when the door goes back up. Are you sure it is 5 and are you talking about the main light - not an LED? Are you sure you put the black plastic cup back on the end of the motor shaft after changing the RPM sensor board? Make sure it is pressed all the way on. Release the door from the opener and see if there is any binding as you lower and open it.

Don, thanks for your reply.

I definitely have the black plastic cup on and it's pressed all the way on.

The little yellow led in the back by the red button and the terminal screws 1,2,3 flashes 5 times, pauses then flashes 5 again.

The main light just turns on when I try to lower the door, it doesn't blink , flash or anything. Just stays on for a bit, and if I don't try to lower the door again, it will shut off.

Do you think I got a bad rpm sensor? The guy sent me 2 of them and I tried them both. I did keep my original cap on though, I figured that would still be good

Thanks, Mike

I've never done this, but I've read that you can short some of the wires on the light sensors to make them think there's always a good light connection. Obviously this isn't recommened as a long term solution, but to test whethter or not the lights are the issue, it might help. I don't have the details and it may only work for certain models, but google is a good source of information.

The LED flashing 5 times is sending the code for RPM sensor or motor overload. The motor is running so you can forget the overload bit. I'm a little leery of you getting 2 bad RPM sensors but that is always a possibility when dealing with e-bay and used parts. If you can, watch the motor when it starts to run. Make sure the shaft is not moving so far that the plastic cup is moving from between the infra-red eyes on the RPM sensor.

FYI there is no way to bypass or defeat the door sensors no matter what you might read on google as kidhorn says.

I changed my logic board on my Craftsman 1/2 horsepower door opener because of same symptoms Mike had. Before replacing it I removed door sensors to make sure that was not the issue along with that fact that door moves up and down manually fine. I checked DC voltage between terminals 2 & 3 and it was above 6 volts so according to what I read that meant bad logic board and I ordered a new one from sears and installed it and am still having the problem.

"I removed door sensors to make sure that was not the issue" not sure what you meant by this, but the sensors need to be connected and aligned for the door to close properly.

I simply removed the sensor wires from the from the main controller thinking this was a way to determine if the sensors were there problem.

Operation will not be any different if you remove them or if they are broken as the door will not operate properly without the sensors inplace and functional. The lights need to be on for both the sender and reciever sensors and they need to detect each other. One simple check is to have them connected to the main unit and bring them together with the lenses facing each other. The sender (if powered) will always have a lit LED. The LED on the reciver will only light when it detects the sender. The reciever light needs to be on solidly with no flickering. If the sensors are not functioning the door will not close close. It will try, stop, and the opener incandescent light bulbs will flash 10 times. Holding the wall button down will override the sensors and allow the door to close. The wall button muist be held for the full closure of the door. Hope that helps.

Yes one sensor was flickering, I tapped it and it stayed lit like you described. Now door goes down 90% of them way then stops and goes back up. I have also noticed that one sensor light is yellow is that normal because the one that was flickering is green? Sensors are both original I installed them in 1998.

yes one sensor is green and the other is yellow. With both lit, if you put your hand between them the receiver will go out and the sender stays on. If the door reverses and the lights blink 10 times there's still a problem with the sensors or something tripped them on the way down. If the door had hit a stop it would not have reversed. If the door hits something hard, it will reverse.

See if you can find a manual online and go throught the setup steps again. Check all of you conenctions and the installation of the new logic board. You might consider calling a local garage door company to come and debug it for you.

good luck

Ok thank you for you assistance.