Mystery sensors on front bumper

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j.a.mcguire
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Mystery sensors on front bumper

Post by j.a.mcguire » Fri Jan 12, 2018 12:17 pm

There are two sensors on either side of the front bumper with a piece of transparent hose going between them. At first I thought these were the jet washers but on closer inspection they're not in the right place. They're situated slightly above the outer-most parking sensors. I've tried googling the code but get nothing, any idea what they are?


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moose
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Re: Mystery sensors on front bumper

Post by moose » Fri Jan 12, 2018 12:44 pm

The washers live behind flaps in the bumper.

Any chance of a picture and I will check on mine, I have front sensors as well.

Bob
R Sport 240ps Bluefire with Templar wheels. Parking pack, blind spot monitor, heated windscreen, folding mirrors, splash guards, privacy glass.


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Vespa
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Re: Mystery sensors on front bumper

Post by Vespa » Fri Jan 12, 2018 2:28 pm

The small oblong covers around 1 1/12" x 2 1/2" are the headlamp washers. They operate independantly of each other and only after every 5th ( If I remember correctly) operatin of the screen washers whe the head lamps are on. So left will operate and then the next time the right.

CNV00028.jpg

You can see the oblong just under the head lamps. The large round cover is the tow hook attachmentThe small round blanks under the grill are sensors and just out of easy view in the black honeycomb with brushed aluminium is another senor for the park aids.
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The Austrian
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Re: Mystery sensors on front bumper

Post by The Austrian » Fri Jan 12, 2018 8:05 pm

The two sensors with the silicone tube in between are there to measure an impact produced by a pedestrian. If there is an impact, they send a signal to the SRS module which then decides if it is necessery wether to trigger the pyrotechnical bonnet lifters or not.

So these sensors are essentially for pedestrian safety in the case of an impact.
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j.a.mcguire
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Location: Newcastle

Re: Mystery sensors on front bumper

Post by j.a.mcguire » Fri Jan 12, 2018 11:19 pm

Thank you. Hadnt realised the actuators on the bonnet were pyrotechnic sounds bloody dangerous!

Im curious as to what purpose the interconnecting hose serves? Its not rigid enough to carry a vacuum i wouldnt have thought?


The Austrian
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Re: Mystery sensors on front bumper

Post by The Austrian » Sat Jan 13, 2018 5:16 pm

Well it‘s not as dangerous as it might sound. It is pretty much the same system like you have in your Airbags.

The silicone hose in between the two sensors has a pretty simple duty: If you have a front impact there will be a pressure in the hose which is detected from the sensors. This way the system is able to detect wether if you have hit a pedestrian or something bigger/smaller.
MY18 XE R-Sport 20d AWD in Caesium Blue


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Vespa
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Re: Mystery sensors on front bumper

Post by Vespa » Sun Jan 14, 2018 8:36 am

I must have misunderstood the description. Sorry about that. :oops:
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