Best place to place fuel pump kill switch in a car?
I drive a car that thieves love to steal—2007 Infiniti G35 6MT coupe. I want to add a hidden fuel pump kill switch. My goal is to add a toggle switch to the low-amperage control circuit side of the fuel pump relay. As you can see in the wiring diagram above, the ignition switch meets a splice, one line feeds the control circuit of the fuel pump relay (B/OR wire—black wire with orange stripe), which then goes to the ECM (ECU) for a ground, and the other line supplies the load to the fuel pump (technically, through the ignition relay, not directly from the ignition switch).
- If I place the toggle switch after the fuel pump relay but before the ECM, in order to interrupt the ground connection, do I need to worry about voltage in the relay coil or any kind of voltage flyback?
- Would it be safer instead to place the toggle switch before the fuel pump relay (after the ignition switch), in order to prevent any voltage from entering the relay coil when the kill switch is open?
u/mojave22 — 3 days ago