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luca1290

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The factory one was broken when it arrived. Half a year of standing on the square killed the original battery. I found a battery with exactly the same parameters as the factory one. Do you think that this is the reason why when the ignition is turned on, the battery will not be able to produce a sufficient spark and the car simply decides to turn off? It would make sense.
This looks like a very much more graceful shut down that the one produced by a loose connection of low battery, especially if the car operates correctly after you start it.

There is something that some ECU is reading somewhere that causes this behavior that she doesn't like and produces this output.

For the OP, other than comparing the programming with a known good one (what you could do is also reprogram you ECUs with the good one from the factory if you have FDRS and an original VCM interface - I have and I'm sorry we live that far apart!!) is closely inspect with Forscan all the PIDs related to "engine allowed to start" in the PCM and BCM.

I would not try to rule out the possibility the previous owner modified the car to have this exact behavior - be it in software OR hardware somewhere.
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ORRadtech

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When you check the wiring under the dash be sure to take the time to continuity check each wire related to the start and brake switches. Also check each connector to be sure all the pins are seated fully.
My thinking is that during the air bag deployment and all the other work done something could have been pulled breaking a wire inside its insulation or unsettling a pin.
Do you have a FSM with the wiring diagram
Also, is this the only quirk you have found?
 

ORRadtech

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I think you would be well advised to get an FSM for your car. They have tons of information including flow charts for testing and diagnosis of all the major systems (including starting), pin point testing, wiring diagrams, wiring harness and connector routing and locations and pretty much everything to do with the car.
You can find downloadable, searchable versions online starting around $100. There are also services like Alldata where you can find TONS of information starting at (I think) $25 for a 1 year subscription.
 

Bean_M

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Did you ever work out the cause? I'm having exactly the same problem with my manual 2020 GT. I turn the ignition on to access accessories or change modes, then when I press the clutch and push/hold the start button the car turns off instead. I can start the car when it's off.

No previous crash damage reported and the car otherwise operates normally.
 

shogun32

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Did you ever work out the cause? I'm having exactly the same problem with my manual 2020 GT. I turn the ignition on to access accessories or change modes, then when I press the clutch and push/hold the start button the car turns off instead. I can start the car when it's off.

No previous crash damage reported and the car otherwise operates normally.
to quote the smartest guy ever Steve Jobs, "You're holding it wrong".

The cubicle-dwelling bus-riding software engineers consider your order of operations to be erroneous. Please redo your car-use procedure to the correct one.
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