Inertia safety switch

INERTIA SAFETY SWITCH

The vehicle is equipped with an inertia switch located inside the passenger compartment beneath the driver’s seat. This sensor reduces the possibility of fire (caused by fuel emerging from the injection system) by de-activating the fuel feed pump. The switch consists of a steel ball fitted inside a tapered housing. It is held in position through the attractive force of an permanent magnet. The ball is released from the magnetic force in the case of violent impact, when it opens the normally closed (NC) electrical circuit to cut off the fuel pump earth connection and thus the fuel supply to the injection system. To restore the pump earth connection, push the seat back and press the switch until it clicks on.

Removing-refitting

1. Move driver’s seat back fully, unscrew the bolts indicated and remove the plastic protection.
2. Unscrew the bolts indicated, disconnect electrical connection and remove the switch.

After even an apparently light collision, if a smell of petrol is noted or fuel leaks are seen, do not activate the switch again until the fault has been found and corrected in order to avoid the risk of fire.

Inertia switch components

1. Inertia switch assembly
2. Sheath
3. Button
4. Upper end
5. Fitting end
6. Permanent magnet
7. Permanent magnet seat
8. Steel ball

C= Common terminal
N.C. Normally closed
N.A. Normally open