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-   -   Airbag warning light - Passenger seat (https://forum.a8parts.co.uk/showthread.php?t=114)

moltuae 2nd November 2016 07:14 PM

Quote:

Originally Posted by David's8 (Post 119250)
1. Shorting out the thigh pad part of the sensor now gives me "seat occupied" indication at all time regardless of whether there is a person in it. Is this a problem?

Just get yourself a fake person for those times when you have no passengers ;)

A blow-up doll should do the trick ... with the added bonus of providing you with extra passenger-side 'airbags' PLUS the freedom to drive down HOV lanes when you have no real passengers!

David's8 2nd November 2016 08:28 PM

Quote:

Originally Posted by moltuae (Post 119259)
Just get yourself a fake person for those times when you have no passengers ;)

A blow-up doll should do the trick ... with the added bonus of providing you with extra passenger-side 'airbags' PLUS the freedom to drive down HOV lanes when you have no real passengers!

:ROFL: ...and quickly earn myself a stiff interrogation from SWMBO when she gets reports that Ive been seen with young blonde in the car :tuttut:

moltuae 2nd November 2016 09:05 PM

Quote:

Originally Posted by David's8 (Post 119264)
:ROFL: ...and quickly earn myself a stiff interrogation from SWMBO when she gets reports that Ive been seen with young blonde in the car :tuttut:

Ah, no but here's where it gets even better ....

You show her your new polythene friend and explain why she's sat in the passenger seat. So now not only does she think you're wonderful for devising such an ingenious solution but if you are ever spotted driving around with a young blond in the car, SWMBO will just assume hubby was driving around with his inflatable chum. +++

I can't image how that could possibly go wrong .... However, I should probably add the disclaimer that I cannot be held responsible in any way should the aforementioned plan fail. ;)

Architex_mA8tey 3rd November 2016 01:35 PM

1 Attachment(s)
Quote:

Originally Posted by moltuae (Post 119259)
Just get yourself a fake person for those times when you have no passengers ;)

A blow-up doll should do the trick ... with the added bonus of providing you with extra passenger-side 'airbags' PLUS the freedom to drive down HOV lanes when you have no real passengers!

Here you go - http://www.dailymail.co.uk/news/arti...hirt-seat.html

http://forum.a8parts.co.uk/attachmen...1&d=1478183713

HPsauce 3rd November 2016 04:21 PM

Those fake passengers probably won't work; the cameras they use to check now have heat sensors as well so they need to have warm faces. ;)

Going back to earlier posts I found references to 470ohms as a "safe" resistance value for the seat occupancy circuit. I also found my tests:
Quote:

Originally Posted by HPsauce (Post 43243)
I did do some vague resistance testing, as follows:
The thigh pad was open circuit when unloaded, pressed as hard as I could manage (in some places) I could get it down to maybe 20K ohms.
The main seat pad was in the "several K ohms" range when unloaded and dropped to maybe 200 ohms (IIRC, not sure exactly what range my meter was on) with my big fat backside on it. :o

Now if my thigh pad was throwing a fault when open circuit is absolutely cannot be connected in parallel to the main pad if that has a "several K ohms" value when empty and around 200 ohms when occupied as it would make no difference. If simple, it has to be in series.

There may be some complex stuff going on, but I doubt it. Simple series connection should suffice if the resistances are proportionate to the expected loads on each component. I would expect the smaller pad to have a low resistance when unloaded and be even lower when compressed, maybe of the order of 200 down to 50 ohms.

David's8 3rd November 2016 04:30 PM

Thanks Andrew for bring the thread back to reality. If I have shorted out the front pad - as you did - and I get the reading of "occupied" whether or not there is someone in the seat (The Laird kindly obliged) what do you deduce from that? (This electrickery is a bit of a mystery to me - I should have listened a bit more closely at school about V=IR or whatever)

HPsauce 3rd November 2016 04:49 PM

David, not sure I can deduce anything as I didn't look at VCDS during my tests and have no details of the circuits in the seats, or how the sensors work. It could be that the main pad has a non-critical fault as well, or my analysis is wrong.

David's8 3rd November 2016 05:54 PM

Maybe I am being overly concerned but I just want to ensure that the system works as it should when my nearest and dearest are in the seat. :)
I guess that with it indicating "occupied" it should. +++

Goran 4th November 2016 09:12 AM

Interesting that one of the options in VCDS is 'not coded' I wonder if we could re-code the ECU to think that the pad sensor was not installed (like for the driver's seat), and if that would work.

oldnick 4th November 2016 02:22 PM

well , bit the bullet and cut the wires as per andrew and david ; tested the resistance of the thigh circuit ....no current passes ; scotch locked the ends which are presumed to be from the main seat sensor and light goes out as required
vcds now says seat occupied but also that there is the same fault as before

but what about the sign underneath the rear view mirror ....I had forgotten that ....it says passenger seat airbag off when~I turn ignition on then promptly goes off ...is that what it did before? didn't take note !!!!

anyway read that the airbag light is supposed to go out when you start the engine , is that correct ? mine always went out when I just brought up the ignition lights

just started to rain , so ~I suppose ~I should be grateful to have had a hot sunny week to work in the courtyard getting rid of assorted lights . much nicer than in the garage


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