In turn, if the cutoff switch is thrown - an unmodified alternator will lose it's excitation 12V.your method will work but the idea is to completely kill all power starting at the battery. The purpose of the cutoff switch is to REMOVE power, not sit there unused while you tinker around removing a battery to showcase how an alternator works. If the battery is suddenly removed from the car and the cutoff switch has not been thrown from on to off, than yes the alternator will continue it's power output. Then I would tell you that you are wrong in assuming this diagram is incorrect. In turn, if the cutoff switch is thrown - an unmodified alternator will lose it's excitation 12V. The alternator's output pole is on the IN side of the solid state relay, meaning that if the switch if OFF the alternator is now removed from the power distribution of the car - it will feed back to the battery, which in turn is also cutoff from supplying power to the car's electrical system. IF the car is still using an unmodified alternator, the alternator's exciter 12V will also be off of this distribution point. The switch will control the solid state relay, either closing or opening the circuit which will allow battery voltage to reach your cabin side junction stud > power distribution to your components. a1320addict, the switch will kill the battery but what will kill the alternator? what if I tell you that after the car has been started you can remove the battery from the car and the car will still continue running with the alternator.Then I would tell you that you are wrong in assuming this diagram is incorrect. This way when the car is running, if you turn off the switch, the car will die, this is the purpose of running a kill switch. run an additional wire from the positive terminal of the battery BEFORE the switch directly to the alternator. The only way you will kill the engine and all power to the car is: Now you have a funtioning system that will only kill power to the battery, noticed I haven't said anything about the alternator. run another wire from the distribution point to the 'stock' fuse box just as if you were running it if the battery was in the original location. Run a wire from the distribution point to the starter. connect the other side of the switch to the battery (I use a jump start terminal as my distribution point). one heavy gauge wire from positive side of the switch to a junction or distribution block.

How you do this is simple no matter where your battery is mounted, mine is in the trunk. The only thing you need to kill is the power from the battery and the alternator. As I am looking at all these Diagram every time this subject came up people are complicating the whole idea and functionality of the system.

Car battery kill switch