CAN communication from automatic gearbox One of the CAN messages expected from the automatic gearbox control unit disappears or is missing. The engine must be switched off and the ignition turned off to change gear in the transfer gearbox. The fault code is only generated in vehicles with an automatic gearbox. If fault codes 11060, 11070, 11080, 11100 and 11110 have been generated, there is probably an open circuit on the CAN cable to the AWD control unit.