Sega Genesis thinks Down" is pressed on controller 1

[dashv]

This is an odd one...

I have 4 controllers for my genesis.

1 3 button official controller
1 6 button official controller
1 6 button 3rd party controller
1 3 button Sega arcade stick

With no controller plugged into controller port 1 The genesis acts like down is being pressed and held. No matter what game I have in it.

With the arcade stick plugged in it behaves the same.

Every other controller works as expected.

The arcade stick works perfectly in port 2.

The official 6 button controller used to have the same problem but magically started working perfectly.

I have taken the console apart and cleaned the board. There do not appear to be any shorted pins.

Any ideas?

[ffxik]

Is there any debris inside the controller socket itself?  When you had the console apart did you check for any broken solder joints? How do the other controllers behave in the second port?

It's odd for this to happen to say the least, and I'm not too sure how to approach it. 

[dashv]

No visible debris in port. No obviously broken solder points.

All controllers work perfectly in controller port 2. Later today I will clean the port with a toothbrush.

[ffxik]

Have you made any progress on this?

[zenimus]

This is an issue with the 6 button controllers. Certain games (like Golden Axe I think) won't behave correctly with a 6 button controller unless you start up the Genesis while holding down the "mode" button.

[dashv]

Actually my problem is the opposite of what you think.

Only 6 button controllers work correctly on my system.

3 button controllers and the 2 button sega master system controller all act like down is being pressed basically making them unusable.

No progress made other than to add sega master system controllers to the list of ones I can't use.

Which is a real bummer because it means I can't play SMS double dragon or any other game that requires an SMS controller in port 1.

[retrogamer418]

What model of Genesis is this?

[dashv]

Model 1.

I haven't managed to fix it. Bought a model 2 which I now use instead.