Transmission Fault Status If the EAT ECU detects a fault with the transmission system, it will enter a default mode to prevent further damage to the transmission and allow the vehicle to be driven. When a fault is detected a CAN message is sent from the EAT ECU and is received by the instrument pack. The instrument pack illuminates the MIL and displays 'TRANS. FAILSAFE' in the message centre. Some transmission faults may not illuminate the MIL or display a fault message, but the driver may notice a reduction in shift quality.