C5 (X7) Pyramid shaped sensor under floor near exhaust?

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Jay-Bruce
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C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by Jay-Bruce »

Long story short in prowling about under the car I've noticed a pyramid shaped sensor looking "thing" under the floor, sitting on the boot floor exhaust heatshield, beside the aluminium galvanic corrosion generating annode pipe union that joins the fore to aft hydraulic pipe from the BHI to the rear firmness regulator, and I wonder what the heck it is?
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Re: C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by GiveMeABreak »

No idea without a picture Jay.
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Re: C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by bobins »

A Chinese spying device ? :lol:
Sadly no longer a C5 owner :(
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Re: C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by myglaren »

Pharaoh detector?
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Re: C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by Jay-Bruce »

I'll grab a better picture when I'm back at the workshop tomorrow, but here's a blurry picture of the xi-jing-pharoah-ping-ping-thing...
Image
Bottom edge of picture is towards front of car, top of picture is towards the rear, left of the picture is towards the left of the car, and right of the picture is towards the right hand side of the car. The pipework in the bottom of the picture is the plastic return lines from the rear firmness regulator, and the stippled / textured ally plate the sensor is bolted to/through is the heatshield for the rear exhaust box that runs under the boot floor.

My guestimate would be something like a yaw sensor for the ESP? Or given it's location relative to the wheelbase of the vehicle maybe an accelerometer would be a better fit?
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Re: C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by MattBLancs »

IMG_20230409_185445840_HDR.jpg
IMG_20230409_185430405.jpg
Here is my underfloor toblerone for comparison purposes :)
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Re: C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by Jay-Bruce »

Oh, you've got one as well Matt? Guess your C5 was also specced up with a Chinese Communist Party pharoah detector? Seriously though, what the hell is it?
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Re: C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by Sloppysod »

Jay-Bruce wrote: 09 Apr 2023, 19:27 Oh, you've got one as well Matt? Guess your C5 was also specced up with a Chinese Communist Party pharoah detector? Seriously though, what the hell is it?
It's a "what-sa-ma-callit, thingy-am-Bob", something to do with the woggle pin - I think🤔🍻🥂🍺.
Stu 🏴󠁧󠁢󠁷󠁬󠁳󠁿

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Re: C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by GiveMeABreak »

Well, I'm stumped at this point - can either of you see where that cable / pipe goes to?

The only thing near there on a V6 X7 and not on 4 Cyl X7s is a pressure sensor in that region.
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Re: C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by Jay-Bruce »

It's present on my V6 HDi and Matt's 2.2 HDi... I'll have a look around mine tomorrow, see if I can discern any numbers off of it.
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Re: C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by aerodynamica »

:-D I've got one too

I thought it was either some kind of receiver for the tyre pressure monitors? Or was a motion sensor.
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Re: C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by Jay-Bruce »

Definitely not that sensor, it's in totally the wrong place...
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Re: C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by MattBLancs »

GiveMeABreak wrote: 09 Apr 2023, 20:17 Well, I'm stumped at this point - can either of you see where that cable / pipe goes to?

The only thing near there on a V6 X7 and not on 4 Cyl X7s is a pressure sensor in that region.
I'll have a look next time I am under "properly" (i.e I did the "never do with a hydraulic Citroen" and just leant underneath. )
Sloppysod wrote: 09 Apr 2023, 19:41
Jay-Bruce wrote: 09 Apr 2023, 19:27 Oh, you've got one as well Matt? Guess your C5 was also specced up with a Chinese Communist Party pharoah detector? Seriously though, what the hell is it?
It's a "what-sa-ma-callit, thingy-am-Bob", something to do with the woggle pin - I think🤔🍻🥂🍺.
its a good name but too long! I'm going for "the pointy do-dar" at moment :-D
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Re: C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by Jay-Bruce »

aerodynamica wrote: 09 Apr 2023, 20:25 :-D I've got one too

I thought it was either some kind of receiver for the tyre pressure monitors? Or was a motion sensor.
Now that is a good shout, could well be that.
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Re: C5 (X7) Pyramid shaped sensor under floor near exhaust?

Post by GiveMeABreak »

Right, forget the pressure sensor theory then as it's not on a 2.2 engine.

I did suspect somebody had mounted one of those aftermarket foot swipe sensors to open and raise the tailgate - but a coincidence if a few of you have it.
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