Seatbelt warning

According to all your comment I ask you ... WHY all cars companies install a sound warning ? It is absolutely useless as people must wear seat belt and no matter what.
I really didn't want to open a controversy about importance of seat belt or Italian people ( I know we are always worst then other european countries ). I was just searching for some tech information about connection of wired buckle on my A2.
 
The seatbelt is not far from the ECU compartment; you could wire as it would be impossible to start the car if seatbelt is not present hehe
 
Evening all,

Agree that this thread did go off rail for a bit but only with passenger safety in mind.

Without forgetting the importance of a vehicles safety features, let’s try to keep further input to the original question posed by @paolo_audi, who wanted to understand the addition of a feature that possibly has provisions in place to finish off what the manufacture started.

Maybe this was going to be a future feature before the production line was planned to close.

Kind regards,

Tom
 
2work said:
Evening,

This is a reasoned question as it does look like there is possibility provision for the A2 instrument cluster to give you an audible seatbelt warning, although putting your seatbelt on should be a 'business as usual' occurrence before pulling away in any vehicle. That said I feel you should have something in return to your query. My answer here is purely an assumption with no hard evidence to back it up. It's an interesting venture though which I hope you undertake and report back on.

Here's the seat belt buckle you mention with a 8Z0 part number:

View attachment 99235

It looks to be a 2 wire operation where one wire might be grounded and the other go to the instrument cluster as you mention (similar simple circuit like the brake pad wear sensor or washer bottle level sensor). When the seat belt key/blade part is inserted into the buckle it creates the circuit with the instrument cluster pin being grounded. The red connector looks like it would fit within the connector carrier under the seat where there is room for 3 connectors. I have 2 sets of heated and electric lumber seats which only occupy 2 out of the possible 3 spaces on the carrier, maybe the third opening was going to be filled by the red connector you see in the above picture, certainly looks to be the same shape/size. The airbag connector is attached onto the side of the carrier and certainly doesn't occupy this third aperture.

The real unknown is will the instrument cluster beep if there is no seat belt inserted into the buckle once connected up, thats if my above theory on the wiring is actually correct.

You can certainly code the instrument cluster to give a seatbelt warning which just displays the seatbelt icon for 3-5 seconds when the ignition is first switched on. I've already coded one of my clusters to do this whilst I was playing with settings for another venture I'm yet to release my findings on.

You have no doubt come across the same information as I'm about to show but for everyone else's benefit, here is where the seatbelt buckle might be fed into the instrument cluster:

Green Connector
View attachment 99236
Pin 27 is named as Belt Buckle.

I cannot confirm if any of my fleet has anything attached at pin 27 but if it does I can only guess that it's already grounded out within the harness.

To test this theory I think that you would need to code your cluster to provide the seatbelt warning and also have pin 27 removed. If it beeps then the theory is correct and it should be a straight forward retrofit to enable this feature that never made it to the production line.

As the wired buckle costs EUR 62.51 before any shipping fees from Audi Tradition I personally wouldn't be looking to give this a go anytime soon but maybe something for the back burner if I ever run out of things to retrofit. I guess that a similar buckle might be found in a breakers yard for pennies but very much doubt it'll sport an 8Z0 part number.

The question of whether or not it is needed or necessary is entirely up to the person wishing to give it a go. I can fully appreciate someone wishing to finish off something Audi started and, for whatever reason never rolled out, even if it doesn't give any further functionality apart from being annoying if you fail to abide by the law and choose not to wear a seat belt. In all honesty, most people try to stop the warning beep, not add to the list of things that can trigger it.

As my cluster is already coded for belt warning I'm wiling to test my theory by removing pin 27 (if there is a connection that is) but it'll be a while before I next have the instrument cluster removed. I do have a cluster bench test setup but this wouldn't help as I have multiple warning beeps due to it looking for the circuits that I don't have connected so would be a waste of time.

If you're familiar with removing the instrument cluster and have VCDS then my above guess work can be quickly tested. If there is nothing in pin 27 then all what I've just typed is completely incorrect and I'd draw to the conclusion that this retrofit will result in nothing.

I’m also unable to find any evident of anyone else giving this a go, perhaps you will be the first as you have already done your homework on this.

Kind regards,

Tom
Click to expand...
You could use the belt clasp, with integral switch, (above), with a piezo beeper, (plenty on the bay), and a small 9 volt battery and connector, (connectors on the bay again), wired in series, under the seat, fixed with the loop side of a hook & loop fixing. Low voltage and independent of the car's electrics, should last ages. Buy the time the battery goes, the habit should be established.
Mac.
 
PlasticMac said:
You could use the belt clasp, with integral switch, (above), with a piezo beeper, (plenty on the bay), and a small 9 volt battery and connector, (connectors on the bay again), wired in series, under the seat, fixed with the loop side of a hook & loop fixing. Low voltage and independent of the car's electrics, should last ages. Buy the time the battery goes, the habit should be established.
Mac.
Click to expand...
This assumes the switch is normally closed, and goes open, when the belt is home.
If it's normally open, then a bit of circuitry would be required. If you could get hold of a switched belt dock, maybe the micro switch could be replaced or modified to give normally closed operation.
Mac.
 
PlasticMac said:
This assumes the switch is normally closed, and goes open, when the belt is home.
If it's normally open, then a bit of circuitry would be required. If you could get hold of a switched belt dock, maybe the micro switch could be replaced or modified to give normally closed operation.
Mac.
Click to expand...
I was thinking, in case I would have no success with cluster instrument, to make the same thing using a +12V under key. Once key is turned you must fast your seat belt otherwise buzzer keep on ringing...
 
paolo_audi said:
I was thinking, in case I would have no success with cluster instrument, to make the same thing using a +12V under key. Once key is turned you must fast your seat belt otherwise buzzer keep on ringing...
Click to expand...
That was my thought too, but my idea would have had the beeper beeping all the time the car was parked, so a link to the ignition is essential. I'll think again.
Mac.
 
Hi,
Looking at the circuit schematic, there is provision for seat belt warning in the A2.
So, adding it would, at least in theory, be possible.
Here's the relevant circuit:
Screenshot 2022-09-14 11.05.10.png

Mac.
 
PlasticMac said:
Hi,
Looking at the circuit schematic, there is provision for seat belt warning in the A2.
So, adding it would, at least in theory, be possible.
Here's the relevant circuit:
Click to expand...
Hi Mac
Maybe Audi were thinking ahead or complying with different countries regulations but you can check your own vehicle if you go into Instruments on VCDS (module 17) and do an 'Output Test' ... you can illuminate the seatbelt warning light and sound the warning 'bongs' ... mine has both fitted but neither activated or linked to the seats ... you can alter the coding to make the seatbelt illuminate for a few seconds after you've switched the ignition on but maybe that's a bit pointless 🤔
 
I have already activated the seat belt warning in the 17 and indeed I have lamps on for few seconds after start. It is a good idea to try with output test if there is buzzer for seat belt. I will try.....
 
paolo_audi said:
I have already activated the seat belt warning in the 17 and indeed I have lamps on for few seconds after start. It is a good idea to try with output test if there is buzzer for seat belt. I will try.....
Click to expand...
Hi Paulo .... yes the bongs start after the seatbelt illumination during the output test.
 
I have checked the wired diagram of cluster instrument. There is only one cable that comes from buckle wired and it seems it a ground. So, if I am not wrong, I suppose that if a ground comes to pin 27 of green connector then there is a warning on dash ( hope sound warning ). If no ground just small red lamps for few second. Probably once the seat belt is fast then the ground is open and doesn't go to the instrument cluster. If my assumption is correct I could try to remove instrument cluster and bring a ground to pin 27 and see what happen. Teorically when ground arrives there should be a warning that could disapper once ground is not present at pin 27 ( fast and unfast buckle wired ).
Here diagram....
 

Attachments

  • seat belt.pdf
    195.1 KB · Views: 85
paolo_audi said:
I have checked the wired diagram of cluster instrument. There is only one cable that comes from buckle wired and it seems it a ground. So, if I am not wrong, I suppose that if a ground comes to pin 27 of green connector then there is a warning on dash ( hope sound warning ). If no ground just small red lamps for few second. Probably once the seat belt is fast then the ground is open and doesn't go to the instrument cluster. If my assumption is correct I could try to remove instrument cluster and bring a ground to pin 27 and see what happen. Teorically when ground arrives there should be a warning that could disapper once ground is not present at pin 27 ( fast and unfast buckle wired ).
Here diagram....
Click to expand...
Yes that's what it looks like to me also ... although maybe the coding for the 'bong' and the dash light would need to be altered to make it work ... not even sure that the 'bong' is related to the seatbelt warning but I can't recall ever hearing that sound before doing the output test.
 
paolo_audi said:
In the 17 I see only one option for seat belt. May in the adaption there is something. Have to check
Click to expand...
The bong during the output test actually sounds like the seatbelt warning in my Skoda Citigo, that's what made me think it's the same for the A2 ...
 
paolo_audi said:
Hopefully !! 🤞🤞🤞🤞🤞
Click to expand...
Afternoon,

I’ll have a few spare hours next week so am going to give this a go and report back.

I’m only doing this for experimentation as I along with my whole family always click in before we pull away on all journeys.

Have purchased A5 drivers seatbelt buckle for £15 from the usual auction website that has the 2 wired loom attached. The strap on the buckle looks a bit longer than the A2’s buckle but will be safe enough. Again only for experimental purposes and will probably go back to the standard A2 buckle soon after.

Should have some results for you by midweek. I may need some assistance uploading a video clip of this as a picture won’t of course reveal the gong tone. If anyone would be able to assist with hosting the film clip and providing me with a link to it then that’ll be great. I’ll be able to send the clip via email, WhatsApp or iMessage.

Until Wednesday/Thursday…

Kind regards,

Tom
 
You must log in or register to reply here.
Back
Top