Allison Transmission Questions I have recently removed my complete 34' Oshkosh chassis with Cummins 230 and MT643. The replacement chassis was a complete '98 Freightliner with Cummins 275 and MD3060 tranny. (Fair amount of work for ONE 70 year old.) Anyhow, it's now finished. The previous coach on the Freightliner was a fire totaled (above the floor) 34' Discovery. As received, I noticed that the tower (touch-pad control) was lying on the floor, removed from the dash mount. There was an orange jumper wire from pine 2 to pin 3 that was cut at the tower connector. Not knowing if this was original installation or occurred during demolition I reconncted the jumper. Upon attempted starting I noticed what looked like double "Z" in the tower window. The local Allison dealer didn't have a clue. After disconnecting the jumper the tower window indicated double "N" and the chassis started. Question: Does anyone know what is the purpose of the jumper and/or when it has a function?