Inertia switch?

[craig]

Right I'm a little confused about the inertia switch, what is the differance between the inertia switch and the fuel relay?

I mean I know that the inertia switch cuts fuel if the car is impacted or rolled etc etc but how does the switch know the car has been hit without sensors in the bumpers etc?

Or is it a case of the switch only activates when the engine stops? ie stalls

Craig

[SDMC001]

Craig

I can only speak for the Rover switch, but I am sure others are much the same. The inertia switch detects harsh movements in the car such as, as you pointed out an impact, but more so, a roll. It has a small ball bearing sitting on a magnetic plate inside witch moves, and rises to move a spring loaded split plate, and breaks the circuit to the fuel pump relay, the engine then dies as the fuel pressure drops due to no pump. So the engine in essence does not stop instantly, but soon, probably two to three seconds.

The function of the relay is just as any relay.

Steve

[alackofspeed]

The Honda OEM switch is just as Steve described the Rover one.

[craig]

Cheers Guys


looking at the switches today to buy one some had three wires and others had 2 wires, is it just a case of one to fuel pump feed and the other to earth?

Craig

[limpabit]

Hi Craig.

It's breaks the yellow/Green wire between the main relay feed and pump.

Cheers

John