Nodes of the electromagnetic drive of the front drive axle
1. Pilot lamp; 2. Processing unit (on vehicles with front axle selector); 3. Switch (on vehicles with front axle selector); 4. Block of solenoids of the electromagnetic drive; 5. Vacuum tank; 6. Drive switch; 7. Drive; 8. Selector switch (on vehicles without front axle selector); 9. Relay; 10. Front axle switch (on vehicles with front axle selector)
4x4 vehicles "Toyota 4 Runner/ Hilux/ Surf" equipped with an electromagnetic drive of the front drive axle (ADD system).
When the front axle is turned on, the drive blocks the left axle shaft, through which torque is transmitted from the engine.
When using the blocking of the axle shaft, the need for locking hubs is eliminated, however, the loads on the CV joints, covers and differential parts that rotate even when the front axle is turned off increase, and their wear increases.
On vehicles with such a system, axle shafts and covers require especially careful checking.
If the front axle engages and disengages abnormally, the following checks should be performed.
If the measures taken do not give a result, then the car should be handed over to a car service.