No start after jump

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Just a rare gravity gust induced inertia switch trip occurrence?...


So did it ultimately throw a code or does the inertia switch just lock out the fuel pump? What year LC and do they all have a re-settable inertia switch up under that dash? Anyone know the internal construction of said switch or perhaps how the cold could have affected it?
 
So it is upside down day in Flagstaff. The inertia switch was tripped.

Not even in my top ten possibles.

So what was done to fix it? Just incase another member finds them self in a similar situation..
 
What exactly did you do after you jumped the Montero? Did you drive the LC around the block and park it somewhere else? Did your LC immediately stall on it's own?

yotsavg, the switch is located on the DS footwell, above the transmission tunnel. You might have to pull the carpet back a bit to see it. There is a little yellow button on it. It's job is to disconnect the fuel pump in case of a major accident or rollover.
 
Is the 'inertia' sensor intrinsic to the switch or it just a means to reset the output of other sensors?
 
Good question and I don't know. But it lists for $38, has metal mounts and is located in one of the most protected areas of the vehicle.... so my guess, intrinsic?

84562-60010

08181502081.webp
 
Hmmm... for $38 and it being a safety item I'd almost thing it's just a remote reset. The inertia sensor has to be pretty sophisticated to be able to differentiate between a rough road and a roll over. Can you imagine needing to reset it every time you caught a little air?

And I guess there's another assumption I should clarify in the above: is it for rollover protection or impact protection? Or both?
 
Here we go, straight from Toyota... says "Collision"

Page 12

And apparently, it is intrinsic because it looks just like the one in their picture.
 

Attachments

Interesting. So that little ball is the inertia reference. And resetting the switch allows the ball to re-center and hold the switch back in place. So I guess it won't necessarily do anything at all in a roll-over.

This little diagram, however, complicates the understanding of what happened to the OP's vehicle. I was at first thinking stray current had caused the ECU to trip and withhold fuel. But I can't for the life of me see how this can even remotely be related to the jump.
 
Well, I wouldn't say it doesn't do anything in a roll-over. The ball rests in a centering bowl. If you position the switch upside down or on it's side, I would think it would take less of an impact to dislodge the ball, right? =) But yes, simply putting the vehicle on a rotisserie and inverting it won't trip the switch.
 
Yes, you phrased it better. Makes me wonder then what they use to sense for RCSA activation.
 
I realize those browsing from the mobile app can't see the PDF I attached. But basically, push the button for a certain amount of time so the metal ball in the switch gets back into position. There is also a magnet that keeps it in place too.
 
The LC is 1999. The LC was properly hooked up to the Montero, hot to hot, black to ground, the LC was running, like a top as always. As the connection was made, the LC died, and did not come back to life. I tried all the usual things, without luck, so I towed it to my local wrench. They also thought it would be a fuel pump issue, or relay, but after a couple hours of troubleshooting determined it to be the inertia switch. Like I said before, gravity was suspended in Flagstaff on that day. ;)
I don't know what could have happened to trip it, but it was definitely related to hooking it up to the Montero. Now I have one more thing to check in the event of a dead truck.
 
the inertia switch appears to be mechanical. it's just a spring holding a steel ball in place to complete a circuit.

i think the jump start caused the ball to bail out the way it would if you tried to sandwich it between the positive ends of two identical magnets. how you achieved that i don't know.
 
It could also have been something else (like a loose connector) but the shop was trying multiple things between start attempts and the last thing touched happened to be the inertia switch.
 
I realize those browsing from the mobile app can't see the PDF I attached. But basically, push the button for a certain amount of time so the metal ball in the switch gets back into position. There is also a magnet that keeps it in place too.

Oops, that would have been my issue, now that I'm on a desktop I can see it. Thank you again though hoser. This is a pretty interesting thread, I had no idea there was such a device on board.
 
There are inertia switches on most, and maybe all newer, factory fuel injected vehicles. The problem is the switch isn't in the same location for all vehicles.
 
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