The fault occurs when either the displacment left/right or the inclination levers are activated when the key is turned on. The function is blocked and will not work even if the key switch is recycled. No error message is generated. The only way to unblock it is to pull the battery cable out while the key switch is turned on and wait till all the capacitors are discharged.

The cause of the problem is on the lift lever. This has both a microswitch and a pressure sensor. The microswitch was out of adjustment so that the pressure switch was activating before the microswitch. This also caused jerky movement of the lift.

The controllers in this model are ZAPI H2.