What this code means

This fault is displayed when the controller detects a low logic level of Key-Off signal during Start-Up diagnosis.

Applies to: ZAPI ACE0 / COMBIAC0 controller.

Possible causes / checks (from the source)

It is very likely the fault is due to an under voltage, so it is suggested to check: A) Key input signal down-going pulses (below under voltage threshold) due to external loads, like DC/DC converters starting-up, relays or contactor switching, solenoids energizing / de-energizing. B) Check the connection of power cables to the battery terminal, positive and negative, to MC and to controller +Batt and –Batt, which must be screwed with a torque comprised in the range 5,6Nm÷8,4Nm. C) If no voltage transient is detected on the supply line and the alarm is present every time the key is switched ON, the failure is probably in the controller hardware, so it is necessary to replace the logic board.

Need the part?

If diagnosis points to a failed sensor, solenoid, controller or harness part, send us the code (KEYOFF SHORTED), machine model and serial number — we quote genuine and OEM replacement parts for export.