Just bringing this thread back from the dead.

I've got a 102T-F45L with a E115 code on the display. Unit display turns on with the key pad but as soon as any function is attempted such as horn, lift, and pulling down the control handle there will be 3 clicks from a little black box mounted just above the horn and the display goes to E115.

I can reset by using the keypad but it goes back to error code E115 when I try anything.

Anyone have any ideas what I should look at? I was able to snag a control head unit from another unit for a few minutes but that wasn't the problem.