TA shorts out immediately

Not sure what you're saying. 0.4ohms is too low.

If your saying .4 ohms that is a dead short!!you have a short in your engine or your center roller might be shorted to ground, I have found plastic isolation washers cracked on a GG1 engine, which cost me less then a dollar to replace, or your electronic board may have a short, you can isolate your problem using your ohm meter and disconnect one thing at a time till your short clears , then you'll at last know what has the short and can then get the new part or board and replace it!

good luck!

P.S. what is your item number on your engine is , it will help so others on here can give you an exact possibility otherwise you'll have to trouble shoot as I suggested earlier!

Alan

sorry it is (4.0) ohms from center roller to outside wheel.  do not know where the . decimal came from

Sounds like a wire short at the pickup wire, or the board has an AC input short, probably at the rectifier diodes.

If you unplug the AC input to the board and the short clear usually means the board is bad.  If it stays it is a chassis wiring issue.  G

I've had several of the TAS boards that the drivers were shorted, that's been the most common failure with those symptoms for me.  Obviously, George is right that the top suspect would be pickup wiring, clearly something to check first. 

If it ends up being the board, you can check the drivers with a meter to see if they're bad.  Due to the way the TAS boards are assembled, it's difficult to replace one driver, they obviously assembled it with all the drivers bolted to the HS and then soldered to the board.  When I repair them, I just remove the board and replace all the drivers, they're cheap and it's a lot easier to do the repair that way.