• Sign Up! To view all forums and unlock additional cool features

    Welcome to the #1 Fiesta ST Forum and Fiesta ST community dedicated to Fiesta ST owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the Fiesta ST Forum today!


False Crash Detection on track: assistance needed please

haste

1000 Post Club
Messages
1,222
Likes
1,264
Location
Eastern
#21
I've banged the shit out of my car on the curbs and high speed corners at VIR and didn't run into this issue. I wonder if it's car/sensor specific.
 


OP
Woods247

Woods247

2000 Post Club
Messages
2,531
Likes
4,415
Location
Atl
Thread Starter #22
I've banged the shit out of my car on the curbs and high speed corners at VIR and didn't run into this issue. I wonder if it's car/sensor specific.
It seems to be track specific. I can flog the car at Road Atlanta (which has nasty curbs) and it has no issues. The video I posted earlier shows the kind of elevation changes that fire it off. That track is in the UK but it’s a rollercoaster like Barber and Atlanta Motorsports Park.
 


OP
Woods247

Woods247

2000 Post Club
Messages
2,531
Likes
4,415
Location
Atl
Thread Starter #23
I do not have any sensor related errors. I wish I could pull data that shows which sensor fires. Could ForScan do that??
 


Last edited:
Messages
332
Likes
337
Location
Northern Virginia
#24
This just happened to me a Summit Point. Damn thing even dialed 911. When I hung it up, the operator called back. Very frustrating because it was my last track session of the day.

Perhaps it can be disabled with Forscan?
 


OP
Woods247

Woods247

2000 Post Club
Messages
2,531
Likes
4,415
Location
Atl
Thread Starter #25
This just happened to me a Summit Point. Damn thing even dialed 911. When I hung it up, the operator called back. Very frustrating because it was my last track session of the day.

Perhaps it can be disabled with Forscan?
Nope. Unplug a crash sensor, unplug the airbag model under the console or pull the airbag fuse. I had a tuner tell me he could “use software tuning along with hardware changes” to eliminate it but he lied and bated me into buying a tune then refused to refund after telling me tuning the ECU doesn’t effect it. Don’t make the same mistake. It cannot be changed in the ECU. The RCM has to be reprogrammed and I haven’t found anyone who has that ability. Unplugging the hardware is the only option at this time.

You can disable the alarm my pressing the hazards. Once they’re off, you can enable the fuel pump by pressing the start button twice. After the fuel pump is enabled, go back to the pits and reset the ECU with ForScan or a Cobb Access Port. The car will run normally after that but you’ll have to unplug shit or it’ll just pop again in the same turn.
 


Last edited:
Messages
332
Likes
337
Location
Northern Virginia
#26
Nope. Unplug a crash sensor, unplug the airbag model under the console or pull the airbag fuse. I had a tuner tell me he could “use software tuning along with hardware changes” to eliminate it but he lied and bated me into buying a tune then refused to refund after telling me tuning the ECU doesn’t effect it. Don’t make the same mistake. It cannot be changed in the ECU. The RCM has to be reprogrammed and I haven’t found anyone who has that ability. Unplugging the hardware is the only option at this time.

You can disable the alarm my pressing the hazards. Once they’re off, you can enable the fuel pump by pressing the start button twice. After the fuel pump is enabled, go back to the pits and reset the ECU with ForScan or a Cobb Access Port. The car will run normally after that but you’ll have to unplug shit or it’ll just pop again in the same turn.
Thanks for the reply and the message.

I don’t have a center console anyway, so the module located under said console is right there for me to unplug. You’re confident that simply unplugging that fixes the problem? I have racing seats and considered upgrading the steering wheel anyhow, so a lack of airbags doesn’t concern me too much.

I’ve also read pulling the ABS fuse fixes it, but not sure … with the obvious negative that ABS no longer works.
 


Last edited:
OP
Woods247

Woods247

2000 Post Club
Messages
2,531
Likes
4,415
Location
Atl
Thread Starter #27
Thanks for the reply and the message.

I don’t have a center console anyway, so the module located under said console is right there for me to unplug. You’re confident that simply unplugging that fixes the problem? I have racing seats and considered upgrading the steering wheel anyhow, so a lack of airbags doesn’t concern me too much.

I’ve also read pulling the ABS fuse fixes it, but not sure … with the obvious negative that ABS no longer works.
Yes it definitely fixes it. Your dash will light up though. From what I’ve read, the C-Pillar crash sensors are also the yaw rate sensors. I think… A rally guy on FB told me he pulled the entire system out of the car including the ABS module. Personally, I’d like to keep ABS and not have my dash light up. I don’t know if removing the ABS fuse solves this issue. Removing the airbag fuse does, but if your car is stripped just unplug the RCM. Disconnect your battery first so the existing airbags won’t deploy.
 


Messages
332
Likes
337
Location
Northern Virginia
#28
Yes it definitely fixes it. Your dash will light up though. From what I’ve read, the C-Pillar crash sensors are also the yaw rate sensors. I think… A rally guy on FB told me he pulled the entire system out of the car including the ABS module. Personally, I’d like to keep ABS and not have my dash light up. I don’t know if removing the ABS fuse solves this issue. Removing the airbag fuse does, but if your car is stripped just unplug the RCM. Disconnect your battery first so the existing airbags won’t deploy.
Perfect, thanks. I have a roll bar and 6-point harnesses anyway, so don’t really need the airbags … and the lack of OEM seats causes the airbag light already
 


OP
Woods247

Woods247

2000 Post Club
Messages
2,531
Likes
4,415
Location
Atl
Thread Starter #29
You’ll see the wrench and traction control lights as well.
 


Messages
332
Likes
337
Location
Northern Virginia
#30
You’ll see the wrench and traction control lights as well.
The ability to completely disable stability control remains, correct? Or does that happen with the "crash mode" disabled in this fashion anyhow?

EDIT: I pulled the RMS. The traction control light is on as you said. When I attempt to disable the stability control, the Sync screen shows it as disabling, but then the “traction off” light does NOT display at the bottom of the speedometer like before.

So, I’m confused as to whether the stability is already off with the RMS out and, if not, does holding the button down 6 seconds turn it off as before despite not seeing the usual indicator?
 


Last edited:
OP
Woods247

Woods247

2000 Post Club
Messages
2,531
Likes
4,415
Location
Atl
Thread Starter #31
The ability to completely disable stability control remains, correct? Or does that happen with the "crash mode" disabled in this fashion anyhow?

EDIT: I pulled the RMS. The traction control light is on as you said. When I attempt to disable the stability control, the Sync screen shows it as disabling, but then the “traction off” light does NOT display at the bottom of the speedometer like before.

So, I’m confused as to whether the stability is already off with the RMS out and, if not, does holding the button down 6 seconds turn it off as before despite not seeing the usual indicator?
Unplugging it should completely disable traction control as well but that’s a great question. I didn’t spin my car but I was able to lift off oversteer and slide it through some turns like I normally do without TC interference. I didn’t bother pressing the button since the dash led was already lit.
 


Messages
332
Likes
337
Location
Northern Virginia
#32
Unplugging it should completely disable traction control as well but that’s a great question. I didn’t spin my car but I was able to lift off oversteer and slide it through some turns like I normally do without TC interference. I didn’t bother pressing the button since the dash led was already lit.
Its a different LED … the “car with squiggly lines” that lights up normally when you turn stability control off is at the bottom of the speedometer and contains the word, “OFF.”

The one that comes on with the RMS out is at the top of the speedometer and has no ‘off.’
 


OP
Woods247

Woods247

2000 Post Club
Messages
2,531
Likes
4,415
Location
Atl
Thread Starter #33
Its a different LED … the “car with squiggly lines” that lights up normally when you turn stability control off is at the bottom of the speedometer and contains the word, “OFF.”

The one that comes on with the RMS out is at the top of the speedometer and has no ‘off.’
Now I want to go try to spin my car to see what happens. If ABS is disabled it definitely won’t work. I had a bad wheel sensor once and it was all off.
 


Messages
332
Likes
337
Location
Northern Virginia
#34
Now I want to go try to spin my car to see what happens. If ABS is disabled it definitely won’t work. I had a bad wheel sensor once and it was all off.
ABS should still be on with the RMS module out though, right? The only question is whether stability control is off all the time now. It is my understanding that, with the Cobb Accessport most of us use, stability control is now done using throttle and not ABS, but maybe I’m wrong.

It’s weird that the normal light remains off (that lights up when you go into SPORT mode or full stability mode off) but the Sync screen acts like you are turning said stability off ….
I’d hate to get to the track and then have to scramble to put that damn RMS module back in because the stupid stability control is still on and now we can’t turn it off, LOL.
 


Last edited:
OP
Woods247

Woods247

2000 Post Club
Messages
2,531
Likes
4,415
Location
Atl
Thread Starter #35
ABS should still be on with the RMS module out though, right? The only question is whether stability control is off all the time now. It is my understanding that, with the Cobb Accessport most of us use, stability control is now done using throttle and not ABS, but maybe I’m wrong.

It’s weird that the normal light remains off (that lights up when you go into SPORT mode or full stability mode off) but the Sync screen acts like you are turning said stability off ….
I’d hate to get to the track and then have to scramble to put that damn RMS module back in because the stupid stability control is still on and now we can’t turn it off, LOL.
I didn’t remove mine I just unplugged it. If you want to be certain it’s all off, unplug an ABS wheel sensor or pull the ABS fuse too and it’ll all definitely be off. I don’t use Cobb or a tuner’s traction control, so I can’t answer that part. Mine is controlled by the brakes…mostly the rear brakes. With an ABS sensor unplugged, traction control does not work. I know that from experience.

My biggest concern is automatic HPFP shut off in the event of a hard crash if the RCM is unplugged. I can’t find a definitive answer to that question. I don’t know of this car has an inertia switch or if the HPFP and LPFP are only controlled by the RCM.
 


Messages
332
Likes
337
Location
Northern Virginia
#36
I didn’t remove mine I just unplugged it. If you want to be certain it’s all off, unplug an ABS wheel sensor or pull the ABS fuse too and it’ll all definitely be off. I don’t use Cobb or a tuner’s traction control, so I can’t answer that part. Mine is controlled by the brakes…mostly the rear brakes. With an ABS sensor unplugged, traction control does not work. I know that from experience.

My biggest concern is automatic HPFP shut off in the event of a hard crash if the RCM is unplugged. I can’t find a definitive answer to that question. I don’t know of this car has an inertia switch or if the HPFP and LPFP are only controlled by the RCM.
Okay, so let’s summarize:

1) Unplugging the RCM “definitely” disables the CRASH mode feature.

2) Unplugging the RCM alone leaves ABS active.

3) Unknown if unplugging the RCM affects stability control or torque vectoring. Holding the ESC button for 10 seconds show stability deactivating as usual, but then no light on dash. That button wouldn’t stop torque vectoring anyway.

4) Unplugging a single ABS sensor disables both ABS and “definitely” the stock stability control and torque vectoring.

5) Unplugging an ABS sensor does NOT disable the CRASH mode … or does it?

Bottom line, HERE IS THE GOAL: I want: 1) the crash mode disabled and; 2) the stability control and torque vectoring disabled. Sounds like the RCM is an easy fix for #1, but we are unsure if it solves #2. To be sure stability and torque vectoring are off, we have to pull the ABS also?
 


Last edited:
OP
Woods247

Woods247

2000 Post Club
Messages
2,531
Likes
4,415
Location
Atl
Thread Starter #37
Okay, so let’s summarize:

1) Unplugging the RCM “definitely” disables the CRASH mode feature.

2) Unplugging the RCM alone leaves ABS active.

3) Unknown if unplugging the RCM affects stability control or torque vectoring. Holding the ESC button for 10 seconds show stability deactivating as usual, but then no light on dash. That button wouldn’t stop torque vectoring anyway.

4) Unplugging a single ABS sensor disables both ABS and “definitely” the stock stability control and torque vectoring.

5) Unplugging an ABS sensor does NOT disable the CRASH mode … or does it?

Bottom line, HERE IS THE GOAL: I want: 1) the crash mode disabled and; 2) the stability control and torque vectoring disabled. Sounds like the RCM is an easy fix for #1, but we are unsure if it solves #2. To be sure stability and torque vectoring are off, we have to pull the ABS also?
I’d say you summarized it correctly! Disabling ABS does not fix false crash detection. Unplugging an ABS sensor (or fuse) and unplugging the RCM will completely disable TVC, TC and eliminate false crash detection.

I DO NOT KNOW if the HPFP and LPFP will be shut off in the event of an actual crash with the RCM unplugged. Please help me find the answer to that.. There’s a huge risk of fire if they don’t shut off in a crash.

When you unplug an ABS sensor, expect the ABS pump to activate quickly after you start the car and apply the brake. Mine did that once and never again. It’s “normal”.
 


Messages
332
Likes
337
Location
Northern Virginia
#38
I’d say you summarized it correctly! Disabling ABS does not fix false crash detection. Unplugging an ABS sensor (or fuse) and unplugging the RCM will completely disable TVC, TC and eliminate false crash detection.

I DO NOT KNOW if the HPFP and LPFP will be shut off in the event of an actual crash with the RCM unplugged. Please help me find the answer to that.. There’s a huge risk of fire if they don’t shut off in a crash.

When you unplug an ABS sensor, expect the ABS pump to activate quickly after you start the car and apply the brake. Mine did that once and never again. It’s “normal”.
EDIT: I realize I'm waffling here but . . . the more I read about Torque Vectoring, the more I think I'm okay with it left on. Even if it eats brakes a little faster, help with understeer is appreciated in these cars. BUT BUT BUT, it is really unclear to me the status of TVC and stability control if I do nothing more than disconnect the RCM. In other words, if I unplug the RCM to stop false crash detection, but leave the ABS intact, is FVC and ESC still on? If so, when I hold the ESC button for 6 seconds, is it really turning off stability control - cause the usual light is not lit up.

As for the RCM and the fuel pumps . . . I can find virtually nothing on the internet about that module at all, more less its effect on the fuel pumps. Since the false crash cuts fuel, I think we have to assume the lack of a crash detection would mean the pumps keep going. I have found no evidence of the manual inertia button (that kills the fuel pump) I have on my 2008 Mustang. Here's the thing . . . I has leading a pack of 15 cars on Sunday when my car shut down due to its belief I had crashed. I had just crested a hill, and they had just gone double file behind me as they crested that same hill a second later to find me in their path and off pace. I had to barrel into the grass to keep from getting run over. That's certainly a safety risk, so I don't know how we don't eliminate that first and absorb the fire risk in the (hopefully unlikely) event of a real crash.
 


Last edited:
Messages
332
Likes
337
Location
Northern Virginia
#39
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
 


M-Sport fan

9000 Post Club
Messages
14,115
Likes
6,760
Location
Princeton, N.J.
#40
^^^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. [dunno]
 


Similar threads



Top