Someone tried to steal my SMB last night.

[JackTuppVan]

patrick51 The inertia switch won't act as a toggle. The inertia switch is a safety item incorporated into the fuel system .The only time the inertia switch should trip is during a collision. However, there are other occurrences that can trip an inertia switch, such as a blown tire or simply hitting a pothole in the road.

On the top of the inertia switch is a red button. With the inertia switch in the open position, the red button is raised up. It is not supplying power to the fuel pump in this position "TRIPPED" . When the reset button is pushed in (or down), then the inertia switch will let the voltage flow to the fuel pump "RESET". .................... yvrr ... I would have never thought a busted filament alone would cause that condition . that seems like a design flaw . Thanks I will be sure to remember that bit of information.

[mikracer]

The inertia switch will "activate" in another way other than an impact. I was installing a keyless remote system on a 96 F250 an somehow tripped the switch. I'm not sure if it had to do with something with one of the wires I tapped into, but after I buttoned it all up, the truck wouldn't start. When turning the key to the "on" position, the fuel pump wouldn't prime. Luckily, I remembered reading something about the switch so I went back to the kick panel and pressed the red button and reset it. Everything worked as it should after I pressed the button. Just wanted to chime in and say that it could be tripped without an impact.

[boywonder]

I would assume that you could wire another toggle/rocker, etc in series with the inertia switch........

[yvrr]

No, it is easier than that. The instructor for that class got back to me a couple of minutes ago and told me:

"The fuel cutoff switch is an inertia type switch. I simply hit the kick panel in the area of the switch with a soft mallet and it would trip the switch. Probably not good to do this too much, but a handy deterrent when you find yourself in unsavory areas."

So...keep a soft mallet with you at all times...

[moorefc]

Skimmed thru this... Here is my solution from about 10 years ago...still working well. You can switch it in and out. Subtle red push button where you want it when switched in. Push button and start and van runs. Start engine without pushing button and engine starts, sputters and dies and will not restart.......

If you forget to push button you are reminded when the engine sputters....just push button and you are rolling.

I use it when I am suspicious....naturally never tested by a thief, since I installed it....

Cheers

[gcvt]

Originally Posted by moorefc

Skimmed thru this... Here is my solution from about 10 years ago...still working well. You can switch it in and out. Subtle red push button where you want it when switched in. Push button and start and van runs. Start engine without pushing button and engine starts, sputters and dies and will not restart.......

If you forget to push button you are reminded when the engine sputters....just push button and you are rolling.

I use it when I am suspicious....naturally never tested by a thief, since I installed it....

Cheers

Thanks for the .pdf! Since they came back and stole my SMB six weeks later, I'll hang on to your schematic until I find a new van.

[boywonder]

moorefc: Thanks for the schematic, still digesting.

Assuming that you are using the 30A relay to keep the current off of the square push button switch.....anything else going on here that is not obvious? On the schematic, you call the push button switch "intermittant"......the Digi-Key P/N shows that it's a on-off switch (not momentary)....and it appears that if it was a momentary switch it would not work as designed......just want to clarify....

[Scalf77]

looks like he is using the relay as a latch, the output feeds backs to the coil power, so once it is closed it stays close until power is removed when you turn off the key. The momentary switch initiate the closing of the relay.

=greg

[boywonder]

Originally Posted by Scalf77

looks like he is using the relay as a latch, the output feeds backs to the coil power, so once it is closed it stays close until power is removed when you turn off the key. The momentary switch initiate the closing of the relay.

=greg

Thanks......diving a little deeper into the switch specs, the push button is indeed momentary....

So the upside of this is that you don't have to remember to flip a switch to disable the fuel pump; you have to push the button every time to get the van to start.

[moorefc]

I have been off the forum for a bit. The push button is just that, it is momentary. It is used as a latch. The other toggle switch is to bypass this anti theft mechanism and make the vehicle start normally. It is a pretty sweet setup, and if you forget (anti theft on) the engine will start, then stutter, and if you are reasonably quick you just push the push button and it will catch and go.. Otherwise you just restart holding the momentary while turning the key.

Put the push button somewhere easily reached with your left hand. Very intuitive once you have done it a few times.

Most of the time if I am not feeling like I need the anti theft, I have it switched out so the vehicle starts normally with just the key. If you always wanted it on the schematic could be slightly simplified.

I actually re-ordered this for my newer van..Here is my digikey shopping list (dont know if I really need the relay socket, but for 83cents.....)

1 1 PB679-ND 1432782-1 RELAY AUTOMOTIVE SPST 30A 12V 1
Immediate 0 3.70000 $3.70
2 1 PB316-ND VCF4-1001 HOUSING CONN 5POS FOR VF4 RELAY 1 1
Immediate 0 0.83000 $0.83
3 1 506PB-ND 40-2390-00 SWITCH PUSH SPST-NO 2A 14V 1
Immediate 0 1.24000 $1.24
4 1 360-1896-ND S301 SWITCH TOGGLE SPST 15A 125V 1
Immediate 0 4.68000 $4.68
Subtotal $10.45

Cant beat the price for a security system!

Cheers