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Discussion Starter #1
XF Drivers be warned !!!!!!!

The Pedestrian Safety System is installed on UK versions of the XF and maybe other models. Whilst the concept is Maybe good in that it releases the bonnet in the event of a collision with a pedestrian and the lifting of the rear hinges of the bonnet provides a cushion onto which the pedestrian may impact as the Bonnet profile is so close to the engine head, this system may save a pedestrian from serious injury. Presumably the requirement for this system is an EU directive as North American XF's don't have it.

The issue I have with this system is that it is a ridiculous design and extremely expensive to reset should you have the unfortunate occurrence of an unnecessary initiation of the system by for example touching a high profile curb stone. What happens in this unfortunate event is that the sensors assume you have collided with a pedestrian and the result is that the detonators that trigger the Airbags which lifts the rear of the bonnet are fired, the airbags release and the result is that the bonnet rear lifts. All well and good you might say, but to reset the system The operation of the system destroys the Bonnet Hinges, a couple of bolts are Sheared, the sensors are destroyed and in many cases the Bonnet is distorted to such a degree as to necessitate replacement along with the hinges, Bolts Sensors Detonators and Air bags.
A quotation from Jaguar Dealers assuming the Bonnet was not distorted was in Excess of £1500. With a replacement bonnet and respraying the estimated was in excess of £4000. All of this as a result of lightly touching a raised Curb Stone.

Whilst the necessity of the system is questionable, the design is ridiculous. Surely the design should not destroy so much equipment just to raise the bonnet on presumed pedestrian contact. OK the Airbags may be required to ensure a rapid lifting of the bonnet, but that should be designed such that the Hinges, Bolts, sensors, detonators and Airbags not to mention the Bonnet are completely destroyed in the process.

This is what happened to me and I didn't even touch a pedestrian.

My 40 year relationship with Jaguars is coming to an end after a catalogue of design disasters associated the my XF/
 

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The Pedestrian Safety system almost for all markets but it can be deactivated :)
I assume not via the settings menu on the display?
;-)

It's also worth noting that damage to the front bumper may not be an easy fix.
When mine was in the body shop, I was shown a release on just how sensitive to weight these things are.
 

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I assume not via the settings menu on the display?
No, but easy enough with a few 2.2 ohm resistors in strategic places. Should also have auto-reset fuse in series to stop the resistor burning out if the system is activated.
 

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No, but easy enough with a few 2.2 ohm resistors in strategic places. Should also have auto-reset fuse in series to stop the resistor burning out if the system is activated.
With this potential expense, it does make me wonder if it's actually worth trying to brake in the event of a potentially minor collision.

(Evil emojis)
 

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The system is only active between something like 16 and 31 mph, so ensure you don't travel between these speeds while hitting a pedestrian (or similar) and your bonnet is safe :D
 

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The system is only active between something like 16 and 31 mph, so ensure you don't travel between these speeds while hitting a pedestrian (or similar) and your bonnet is safe :D
Now THAT is something that should be included in your driving theory test.

:)

Which now makes me wonder, that's a hell of a speed to hit a curb/kerb?
 

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Here's some reading about my experience with the pedestrian protection system deploying. Caused by hitting a dead badger.
Cost me £600 to rectify and reinstate the system.

https://www.jaginfo.org/showthread.php?t=73122
Badger! Bugger!!

Sent from my Nexus 10 and an XJ Portfolio. . . ☺
 

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As most of us don't have SDD nor experience of editing the CCF, it'd have to be the resistor route.

Now, I'm not so sure on the legality of disabling the system. Was type approval granted because the system was fitted, or was it fitted to improve the Euro ENCAP figures? If the latter only, then there's no legal reason to keep the system functional (moral reasons aside). Modification of the vehicle from factory standard would of course be something your insurance company would be interested in though.
 

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As most of us don't have SDD nor experience of editing the CCF, it'd have to be the resistor route.

Now, I'm not so sure on the legality of disabling the system. Was type approval granted because the system was fitted, or was it fitted to improve the Euro ENCAP figures? If the latter only, then there's no legal reason to keep the system functional (moral reasons aside). Modification of the vehicle from factory standard would of course be something your insurance company would be interested in though.
Exactly.
Would be worth considering though.
 

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I know the resistors work, I tested this in my car. Unplug the bonnet airbags and fit the resistor assembly to the cable in place of the airbag. The system detects the resistors as the airbags so no error is reported. The system can still be triggered which would entail a reset of the impact system ECU, so perhaps my next experiment would be to replace the pedestrian impact sensors in the front bumper with similar. The system could never trigger then.
 

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As most of us don't have SDD nor experience of editing the CCF, it'd have to be the resistor route.

Now, I'm not so sure on the legality of disabling the system. Was type approval granted because the system was fitted, or was it fitted to improve the Euro ENCAP figures? If the latter only, then there's no legal reason to keep the system functional (moral reasons aside). Modification of the vehicle from factory standard would of course be something your insurance company would be interested in though.
And of course you would have to declare to the insurer a modification to safety equipment, very dangerous ground.
 

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But an unscrupulous person may have modified the system then sold the car, not telling the new owner. So if you were that buyer, you wouldn't know, and without dismantling the vehicle and specifically checking the connectors to the bonnet air bags and the impact sensors, you wouldn't know it wasn't working. :D
 

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And of course you would have to declare to the insurer a modification to safety equipment, very dangerous ground.
Insurers probably hate these systems & have to increase premiums to cover the cost of all the erroneous activations.

Of all the activations reported on the forum, not one to my knowledge has involved a pedestrian.

I suppose the technology is at an early stage & the future will involve using the autonomous driving sensors to detect what the vehicle is about to hit & deploy the safety systems accordingly.
 

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I did a comprehensive Internet search for data. There are many articles and papers stating the potential for saving lives, grossly outnumbered by the number of articles, forum items and blogs stating a vehicle had suffered a false triggering of the system, most costing the owner several thousands to fix, the manufacturers generally are not interested in assisting. I could not find a single report or article that said a person's life had been saved due to the triggering of a pedestrian safety system, of the type fitted to Jaguars.
 

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Discussion Starter #19
Another disturbing thought about this ridiculous unthought out system design. I have had my XF for 8 years from new. It is low mileage at 60,000 miles, but its resale value is around £6000. If the Pedestrian Safety System is inadvertently triggered and distorts the bonnet due to EXTREMELY bad Jaguar Design, the repair cost which will be in excess of £4000 will effectively write the car off. What a hideous design.
That is a warning to any prospective buyers of an ageing XF.
 

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Another disturbing thought about this ridiculous unthought out system design. I have had my XF for 8 years from new. It is low mileage at 60,000 miles, but its resale value is around £6000. If the Pedestrian Safety System is inadvertently triggered and distorts the bonnet due to EXTREMELY bad Jaguar Design, the repair cost which will be in excess of £4000 will effectively write the car off. What a hideous design.
That is a warning to any prospective buyers of an ageing XF.

How would you design it then?
 
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