These battery cable-type cutoff switches are for what jyl describe; for complete system system shutoff - not very convenient for everyday trips. In addition, unless you have an auxiliary bypass circuit to feed the accessories, your radio presets and clock settings will be lost and the alarm, if you have one, will not operate.
You should have an electrical wiring diagram to identify the color coded wire between the fuse box and the fuel pump relay. Splice in a simple SPST (On-Off) switch in series to control this circuit. You can do the same to the circuit between the ignition switch and starter solenoid. Locate the switch in a readily accessible, but not obvious area of the interior otherwise you won't use it.
A mechanical steering wheel lock as well as a tire "boot" will help dissuade the more ardent thieves.
.... but not all the time. BTW, if you have a Honda, your car is more apt to be stolen, but let's not make it too easy for jackers with taste.
Sherwood Lee
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