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False Crash Detection on track: assistance needed please

Woods247

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#1
I’m having unique problems with my car and would like to discuss it with an engineer if possible. It’s related to false positive crash detection on certain race tracks with quick directional and elevation changes. Thank you.

UPDATE 11/2022
I learned A LOT at Barber Motorsports Park today:

1) Unplugging a crash sensor DOES NOT prevent the false crash detection issue.

2) Unplugging the RCM (under the console) DEFINITELY DOES prevent the crash detection issue and ABS is retained. I also think traction control still works but I’ll test that next time we have a skid pad open. The dash is lit up with a wrench, airbag and traction control light while the RCM is unplugged. Pressing the traction control button changes nothing on the dash.

Overall it was an extremely productive day and I successfully lapped for a couple of hours without issues once the RCM was disconnected. Prior to that, I couldn’t complete a single hot lap without the car falsely detecting a crash. I still need to determine if an inertia switch for the LPFP and HPFP are required when the RCM is unplugged. If you choose to unplug your RCM, do so at your own risk. I still do not know if the LPFP and HPFP will shutoff in an actual crash with the RCM unplugged. If anyone knows PLEASE comment.
 


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OP
Woods247

Woods247

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Thread Starter #2
Looks like I’m not the only one experiencing this. There’s a track driver in the UK with the same issue. Fortunately he has video of what triggered his incident. Start at 14:20 to see the sequence.
View: https://youtu.be/MVMyKXbB9wE


I’ll gather video of one of the turns that triggers my car later this month and post it here in hopes someone comes along with an idea for a solution other that disabling the crash detection system. I’d like to retain the HPFP automatic disabling feature in the event I actually crash.
 


OP
Woods247

Woods247

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Thread Starter #3
@D1JL would you please move this to the Troubleshooting section? Thank you.
 


D1JL

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#4
Did you try disconnecting a wheel sensor or removing the ABS fuse.
This disables ABS as well as DSC and torque steer.
You should not need any of these on track.
 


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Woods247

Woods247

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Thread Starter #5
Did you try disconnecting a wheel sensor or removing the ABS fuse.
This disables ABS as well as DSC and torque steer.
You should not need any of these on track.
Yeah I unplugged a wheel sensor and it still does it. I haven't removed a fuse though. Any idea if removing that fuse disables auto HPFP shutoff as well?
 


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Woods247

Woods247

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What exactly does it do in this situation?
The car kills power, honks the horn repeatedly, automatically flashes the hazards, disables the fuel pump and shows a message on the screen stating that a crash was detected. I have to pull off track and go through a sequence to enable the HPFP so I can limp the car back to the pits.
 


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Woods247

Woods247

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Does it set a code?
No that's what's so crazy. It just think's it's been in a crash. My AP shows no codes. Also, this happened before I added wider tires, roll bar and aero. It's still doing it even after switching back to an OEM sized AGM battery. In the video I shard above, you can see that quick directional changed combined with elevation change seems to trigger it if you're going fast.

Edit: It also happened before I removed the stock steering wheel and airbag. Basically my car was "normal" except for the hybrid turbo. As I became more comfortable and got faster with seat time, the car started having this problem.
 


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TDavis

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#10
The car kills power, honks the horn repeatedly, automatically flashes the hazards, disables the fuel pump and shows a message on the screen stating that a crash was detected. I have to pull off track and go through a sequence to enable the HPFP so I can limp the car back to the pits.
Whats the sequence just so I know in case it happens to me
 


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Woods247

Woods247

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Whats the sequence just so I know in case it happens to me
I forget exactly. I found it in my owners manual. It is a sequence of pressing the start button multiple times while holding the brake or something like that..
 


D1JL

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#12
Fuel Pump Shut-off Feature


NOTE: Refer to the Description and Operation, Intelligent Access with Push Button Start in Section 419-01A to review the procedures for achieving the various ignition states (ignition OFF, ignition in ACCESSORY, ignition ON and ignition START) on vehicles with this feature.


In the event of a moderate to severe collision, the vehicle is equipped with a Fuel Pump and Sender Shut-off Feature that is initiated by the event notification signal.


The event notification signal is a signal provided by the RCM to the FPDM . Signal communication between the RCM and the FPDM allows the PCM to shut-off the Fuel Pump.


Should the vehicle shut off after a collision due to this feature, the vehicle may be restarted by first turning the ignition to the OFF position and then turn the ignition to the ON position. In some instances the vehicle may not start the first time and may take one additional ignition cycle.
 


D1JL

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#13
In the early days of fuel injection there was an impact switch that shut off the fuel pump in the left footwell.
Now this is all controlled in the PCM & BCM.
Maybe you should consult your tuner to see if this can be bypassed.
 


OP
Woods247

Woods247

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Thread Starter #14
I asked Adam and he said he cannot assist with this. I should ask JST and Stratified if they've dealt with it. I thought I was completely alone until I saw Steve's video.
 


OP
Woods247

Woods247

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Thread Starter #15
Fuel Pump Shut-off Feature


NOTE: Refer to the Description and Operation, Intelligent Access with Push Button Start in Section 419-01A to review the procedures for achieving the various ignition states (ignition OFF, ignition in ACCESSORY, ignition ON and ignition START) on vehicles with this feature.


In the event of a moderate to severe collision, the vehicle is equipped with a Fuel Pump and Sender Shut-off Feature that is initiated by the event notification signal.


The event notification signal is a signal provided by the RCM to the FPDM . Signal communication between the RCM and the FPDM allows the PCM to shut-off the Fuel Pump.


Should the vehicle shut off after a collision due to this feature, the vehicle may be restarted by first turning the ignition to the OFF position and then turn the ignition to the ON position. In some instances the vehicle may not start the first time and may take one additional ignition cycle.
@TDavis this is it!! Mine definitely takes more than one cycle. When it happens I'm just focused on getting the hell off of the racetrack.
 


Jabbit

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#19
Thank you for this. I’ll dig deeper and see where it leads.
My car is basically gutted and I have a track day this weekend. Let me know if you want me to unplug something and run my car. I've never triggered this crash mode though. Local tracks aren't fast enough.
 


OP
Woods247

Woods247

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Thread Starter #20
My car is basically gutted and I have a track day this weekend. Let me know if you want me to unplug something and run my car. I've never triggered this crash mode though. Local tracks aren't fast enough.
At AMP it’s at T16 which is pretty fast (~105mph) but it has bumps and a quick directional change from left to right while climbing then leveling out. It does it there as soon as I make my first flyer around lap 2 or 3.

At Barber is does it at T14a-T15 which is slower but downhill with a quick right to left.

Even if I stay off curbs it’ll do it. If I slow down it won’t. It’s so weird.
 


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