Bypassing the pedestrian safety system
#22
03-05-2014, 09:40 PM
Senior Member
To disable a PPS you should plug a resistor instead of a two elements -
1. Two pyro elements, which opens a hood lock
2. Two pyro elements, which pops a hood up.
I don't remember the exact resistance of them, but it's not a big problem to find it.
All other attempts of disabling a system will trigger a code and a message on a DIC.
1. Two pyro elements, which opens a hood lock
2. Two pyro elements, which pops a hood up.
I don't remember the exact resistance of them, but it's not a big problem to find it.
All other attempts of disabling a system will trigger a code and a message on a DIC.
#23
03-05-2014, 11:26 PM
Veteran Member
#24
03-05-2014, 11:53 PM
Veteran Member
The European rules and regulations regarding pedestrian avoidance have changed the way all European cars are designed, especially low slung sports cars. Hoods (bonnets) have to be taller, flatter...ruining the aesthetics of many. Cars vs. pedestrians is not a match pedestrians can win and these regulations are ridiculous!
And in response to you, Plums, I'd suggest you watch your step off the curb, I'll make sure I'm driving a non-compliant car when we meet someday in the crosswalk. What kind of threats are you making to a member who is having trouble with a system that's destined for failure?! I think you owe him an apology. Your post is just plain disturbing and has no place, in my opinion, in any discussion.
And in response to you, Plums, I'd suggest you watch your step off the curb, I'll make sure I'm driving a non-compliant car when we meet someday in the crosswalk. What kind of threats are you making to a member who is having trouble with a system that's destined for failure?! I think you owe him an apology. Your post is just plain disturbing and has no place, in my opinion, in any discussion.
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Tracee (08-23-2023)
#25
03-05-2014, 11:59 PM
Senior Member
#26
03-06-2014, 04:03 AM
XF Pedestrian Impact system
The description of the PPS (Pedestrian Protection System) includes the following:
The system will always deploy where the control module determines a pedestrian impact. The system minimizes deployment for other impacts that are similar to pedestrian impact, such as traffic cones.
The manufacturer is clearly acknowledging that deployment will occur in situations other than impacting a pedestrian.
The important components in determining deployment are left and right PPA (Pedestrian Protection Accelerometers) and the PCS (Pedestrian Contact Sensor) which runs across the front of the vehicle:
Attachment 74975
(click on the image to enlarge it)
The PCS uses a fibre optic loop to detect an impact by measuring the amount of light returned to the fibre optic transceiver. A reduction in light levels occurs when the PCS is deformed by an impact. The PCS monitors
the level of light returned from the loop, if a reduction of a predetermined magnitude is measured a trigger signal will be sent to the Control Module.
This has to be the weak link in the system and the cause of non-impact deployment.
Disconnecting the Control Module will trigger error code UO25000 (lost communication with PPS) and probably illuminate the CHECK PEDESTRIAN SYSTEM message and red warning triangle in the display.
Disconnecting the PCS will trigger error code B100631 (no signal). It may have no other effects but I'm not one for pioneering experiments with pyrotechnic systems.
Graham
The system will always deploy where the control module determines a pedestrian impact. The system minimizes deployment for other impacts that are similar to pedestrian impact, such as traffic cones.
The manufacturer is clearly acknowledging that deployment will occur in situations other than impacting a pedestrian.
The important components in determining deployment are left and right PPA (Pedestrian Protection Accelerometers) and the PCS (Pedestrian Contact Sensor) which runs across the front of the vehicle:
Attachment 74975
(click on the image to enlarge it)
The PCS uses a fibre optic loop to detect an impact by measuring the amount of light returned to the fibre optic transceiver. A reduction in light levels occurs when the PCS is deformed by an impact. The PCS monitors
the level of light returned from the loop, if a reduction of a predetermined magnitude is measured a trigger signal will be sent to the Control Module.
This has to be the weak link in the system and the cause of non-impact deployment.
Disconnecting the Control Module will trigger error code UO25000 (lost communication with PPS) and probably illuminate the CHECK PEDESTRIAN SYSTEM message and red warning triangle in the display.
Disconnecting the PCS will trigger error code B100631 (no signal). It may have no other effects but I'm not one for pioneering experiments with pyrotechnic systems.
Graham
#27
03-06-2014, 04:05 AM
#28
03-06-2014, 04:28 AM
Senior Member
Putting a resistor instead of acceleration sensor wouldn't help.
The only way to fool a module is to put a resistors instead of hood airbags.
On a XK you should also add two resistors instead of hood unlockers.
As i said before, i don't remember a correct resistance of a airbags, but i'll try to find a correct data.
#29
03-06-2014, 05:30 AM
I suggest you proceed with extreme caution when visiting this country to avoid some serious jail time!
Graham
#30
03-06-2014, 07:43 AM
Veteran Member
threats of bodily harm to pedestrians are never appropriate
And in response to you, Plums, I'd suggest you
watch your step off the curb, I'll make sure I'm driving a
non-compliant car when we meet someday in the crosswalk.
What kind of threats are you making to a member who is having
trouble with a system that's destined for failure?! I think you owe
him an apology. Your post is just plain disturbing and has no place,
in my opinion, in any discussion.
watch your step off the curb, I'll make sure I'm driving a
non-compliant car when we meet someday in the crosswalk.
What kind of threats are you making to a member who is having
trouble with a system that's destined for failure?! I think you owe
him an apology. Your post is just plain disturbing and has no place,
in my opinion, in any discussion.
2) as can be seen by all, my post was at 12:26am, edited to "nm" at 12:44am.
it has not been touched since, and will not be touched again.
tberg chose to respond my post at 12:53am
My post was in response to, and quoted:
It suggests a mental attitude that somehow motorists have the
privilege of inflicting bodily harm if a pedestrian crosses in front
of them. It is not whether someone will actually do it that is
disturbing, it is the fact that they even entertain and voice
the thought.
A scientific study has already been published where drivers
of luxury cars are more prone to rude behaviour than drivers
of more mundane cars. The behaviours exhibited included:
blowing through crosswalks, running stop signs and
leaning on the horn.
It's part of the my **** don't stink mentality and it needs
to stop.
SInce you bring up my original post, then for the record it
went something like this:
If someone comes to close to me in a crosswalk he
can expect that I might roll over his hood and still be
screaming in pain when the cops arrive to take a report
.... or I might walk away.
can expect that I might roll over his hood and still be
screaming in pain when the cops arrive to take a report
.... or I might walk away.
Which is more disturbing?
This time, my post won't be edited to "nm" or at all.
It will stand as is.
I was ignoring the thread and only dropped by to see
what GGG had to say.
I'm gone again, so anyone who still thinks mowing
down pedestrians is fair game can mutter to
themselves.
++
#31
03-06-2014, 07:45 AM
Veteran Member
#32
03-06-2014, 07:51 AM
Senior Member
And, tell you what, XK, XF, XJ, even w/o a PPS are much safer for pedastrians, than some F150 or C3500.
To finish this fight, PPS switches off after a 40km/h. That's a factory behaivor.
#34
03-06-2014, 10:12 AM
Join Date: Oct 2009
Location: Perth Ontario Canada
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Ahhhh- the wonders of the English language.
#35
03-06-2014, 10:43 AM
Thanks for the info, i was hoping to be able to disconnect the sensors so that the system would never see the trigger signal, i haven't been able to find a data sheet or spec on the XF sensors but the ones i know of give a 0v in normal condition going to somewhere near 5v when triggered or simply an open circuit (with some kind of monitoring) going short circuit when operated.
#36
03-06-2014, 10:53 AM
This technology seems to be about as useful as airbags in an airplane....
Let's be serious, if someone get's hit by a car, this "technology" is not going to change the outcome by a significant factor whatsoever. It was clearly designed to capture some sort of gov't kick back / tax break. Generally a company is not going to invest all the money to solve a problem that doesn't exist,..I sincerely doubt that the occurrence of XK/XKR's hitting pedestrians has ever been high enough to warranty the investment.
Furthermore, if the car was traveling at a fast enough rate to cause any substantial damage, the pedestrian is going to hit the glass which will do far more damage than a hood which is practically on a horizontal plane.
Let's be serious, if someone get's hit by a car, this "technology" is not going to change the outcome by a significant factor whatsoever. It was clearly designed to capture some sort of gov't kick back / tax break. Generally a company is not going to invest all the money to solve a problem that doesn't exist,..I sincerely doubt that the occurrence of XK/XKR's hitting pedestrians has ever been high enough to warranty the investment.
Furthermore, if the car was traveling at a fast enough rate to cause any substantial damage, the pedestrian is going to hit the glass which will do far more damage than a hood which is practically on a horizontal plane.
Last edited by M6XKR; 03-06-2014 at 10:56 AM.
#37
03-06-2014, 11:11 AM
Senior Member
This sensor output signal withn 0-5V, which is constantly changing while a vehicle is moving. PPS control module diagnsoe this sensor just like a ECM monitors a HO2S sensor - if the signal is not changing - then it is a sensor malfunction. Also PPS monitors the difference between signal of both of the sensor and, if the vehicle is equipped with an adaptive suspension, compares a signal with suspension accel. meters.
So it's very hard to fool a PPS control module.
If you fool a PPS CU with a small resistors instead of airbags - it will work fine. IF the condition of hood pop-up are met the PPS CU will simlply blow a resistor and will report an error code. Just replace a resistor, reset a CU with SDD and here you go again. SDD is able to reset one CU for a 5 times, after that you'll have to replace a PPS CU.
So it's very hard to fool a PPS control module.
If you fool a PPS CU with a small resistors instead of airbags - it will work fine. IF the condition of hood pop-up are met the PPS CU will simlply blow a resistor and will report an error code. Just replace a resistor, reset a CU with SDD and here you go again. SDD is able to reset one CU for a 5 times, after that you'll have to replace a PPS CU.
#38
03-06-2014, 11:15 AM
Senior Member
This technology seems to be about as useful as airbags in an airplane....
Let's be serious, if someone get's hit by a car, this "technology" is not going to change the outcome by a significant factor whatsoever. It was clearly designed to capture some sort of gov't kick back / tax break. Generally a company is not going to invest all the money to solve a problem that doesn't exist,..I sincerely doubt that the occurrence of XK/XKR's hitting pedestrians has ever been high enough to warranty the investment.
Furthermore, if the car was traveling at a fast enough rate to cause any substantial damage, the pedestrian is going to hit the glass which will do far more damage than a hood which is practically on a horizontal plane.
Let's be serious, if someone get's hit by a car, this "technology" is not going to change the outcome by a significant factor whatsoever. It was clearly designed to capture some sort of gov't kick back / tax break. Generally a company is not going to invest all the money to solve a problem that doesn't exist,..I sincerely doubt that the occurrence of XK/XKR's hitting pedestrians has ever been high enough to warranty the investment.
Furthermore, if the car was traveling at a fast enough rate to cause any substantial damage, the pedestrian is going to hit the glass which will do far more damage than a hood which is practically on a horizontal plane.
#39
03-06-2014, 12:33 PM
This sensor output signal withn 0-5V, which is constantly changing while a vehicle is moving. PPS control module diagnsoe this sensor just like a ECM monitors a HO2S sensor - if the signal is not changing - then it is a sensor malfunction. Also PPS monitors the difference between signal of both of the sensor and, if the vehicle is equipped with an adaptive suspension, compares a signal with suspension accel. meters.
So it's very hard to fool a PPS control module.
If you fool a PPS CU with a small resistors instead of airbags - it will work fine. IF the condition of hood pop-up are met the PPS CU will simlply blow a resistor and will report an error code. Just replace a resistor, reset a CU with SDD and here you go again. SDD is able to reset one CU for a 5 times, after that you'll have to replace a PPS CU.
So it's very hard to fool a PPS control module.
If you fool a PPS CU with a small resistors instead of airbags - it will work fine. IF the condition of hood pop-up are met the PPS CU will simlply blow a resistor and will report an error code. Just replace a resistor, reset a CU with SDD and here you go again. SDD is able to reset one CU for a 5 times, after that you'll have to replace a PPS CU.
I had hoped that i could tackle problem so that the box didn't get triggered as i know the ecu will need replacing if it activates too many times.
#40
03-06-2014, 12:39 PM
If the sensors operate within a 0v - 5v range with 5v being the trigger point if a zener diode of for example 3.3v were placed across the sensor to clamp the voltage to no more than this would that work ? It would allow a varying voltage but not allow it to get high enough to trigger.
Thoughts anyone ?
Thoughts anyone ?
