False Crash Detection on track: assistance needed please

[cidsamuth]

^^^I was going to say something like that, but was unsure of just how it would be patched into the whole system, and whether or not it would screw with the ECM at all, (codes, or other negative effects, etc.) for a car which still had to be used on the street and pass OBD2 plug-in inspections and all.

My interior is stripped, so I have easy access to the wiring going into the pump. I’d think it would be as easy as grabbing one of them and putting the inertia reset button where it can be pushed while strapped into the driver seat.

 

[Woods247]

^^^I was going to say something like that, but was unsure of just how it would be patched into the whole system, and whether or not it would screw with the ECM at all, (codes, or other negative effects, etc.) for a car which still had to be used on the street and pass OBD2 plug-in inspections and all.

Don’t do this to a street car. Period.

 

[Woods247]

Checked for codes after running the car and got U210B. That should tell us what we need to know about the fuel pump.

But, if we run with no RCM, this is the solution to that problem:

https://www.pegasusautoracing.com/productdetails.asp?RecID=87

Just need to figure out which line this switch will intersect to ensure the pump shuts down

My buddy and I are talking about implementing an inertia switch if there isn’t one already. He’s done it before but I haven’t. I have the wiring diagram for the entire car but still hoping I can find someone from Ford that knows the answer before I spend time implementing something that’s unnecessary.

 

[cidsamuth]

My buddy and I are talking about implementing an inertia switch if there isn’t one already. He’s done it before but I haven’t. I have the wiring diagram for the entire car but still hoping I can find someone from Ford that knows the answer before I spend time implementing something that’s unnecessary.

i have a track day here in a week. I going to do one run with the RCM unplugged and see how different it handles. That will go a long way to my next move.

If I decide to leave it unplugged, the inertia switch is cheap and easy once the right wire is determined

 

[Woods247]

Just to update this incase someone searching in the future wants an answer..

The good ol’ internet has provided. Ford no longer uses inertia switches to disable fuel pumps in a crash. The RCM (under the center console) handles this now. Unfortunately, unplugging crash sensors on USDM Fiesta STs does not resolve the false-crash detection problem like it seems to do in the UK. I plan to implement an inertia switch when driving at tracks that require unplugging the RCM to prevent false-crash detection but will leave it connected everywhere else. NEVER drive on public roads with the RCM unplugged and do so at your own risk on race tracks..

This issue was serious enough to make me consider selling the car but since this simple (unsafe) fix will allow me to keep on wheeling, I’ll keep on wheeling…with an inertia switch, fire suit, cage, harness, HANS and fire suppression system of course. 😂

 

[M-Sport fan]

^^^Yes, even on the stickiest tires out there, and the most dialed-in suspension (and even 'aero') in existence, one should never be pulling enough lateral g's on the STREET, to ever require disconnecting the RCM, EVER!