[zipzapzoom]

Hey guys.
I am stupid but i never understood how the car understands that the passenger seat is occupied when you start driving with a passenger.
I mean, in a high end or passenger seat belt warning enabled car, if you are driving alone the passenger seat belt warning doesnot come up but if you have a passenger in the seat the passenger seat belt warning lights up. ( correct me if i am wrong)
I can understand for driver seat the warning is by default and once you engage the seat belt the circuit is complete and the warning light goes off.
But can someone throw some light on how the car gives warning for passenger seat belt.
regards

[AbhiJ]

The front passenger seat has a weight sensor.

When a person sits on the seat and the sensor activates the seatbelt warning..

[Shan2nu]

Even airbags use this sensor. Some cars wont deploy the airbag if it doesn't sense pressure beyond a specified weight. So even if a child (lighter than the specified weight) is sitting on the front seat, the airbag is programmed not to deploy.

Shan2nu

[scorpio_fan]

Originally Posted by Shan2nu

Even airbags use this sensor. Some cars wont deploy the airbag if it doesn't sense pressure beyond a specified weight. So even if a child (lighter than the specified weight) is sitting on the front seat, the airbag is programmed not to deploy.

Shan2nu

@Shan2nu,
I have a question, some cars have a button for enabling the passenger airbag. If it is enabled via sensor why this button is required? Does it function as a master switch?

Thanks,
Vijay

[Shan2nu]

I dont think cars that use sensors in the seat need have this switch. The sensors decide whether the airbags should or shouldn't deploy.

This might help - Q&As: Airbags

Shan2nu

[zipzapzoom]

Thanks for info guys,
so technically speaking, if one puts some heavy weight on the passenger seat, the sensor will get activated and the warning will come on. right??
regards

[geeash]

@Shan2nu,
I have a question, some cars have a button for enabling the passenger airbag. If it is enabled via sensor why this button is required? Does it function as a master switch?

Thanks,
Vijay

In my linea too i can activate and deactivare passenger airbag in the MID menu

[Tanmay K]

Is it possible to install an audible seatbelt alarm in a car which didn't come with one?

The 2010 Manza Aura doesn't have airbags so it won't have the weight sensor. However, Aura+ came with airbags and I was wondering if the seatbelt warning system from that could be installed on an Aura.

[Gannu_1]

If it's just an audible warning through a buzzer that you need, you can get it done by replacing the seatbelt anchor that comes with the normally-closed switch. Connect it to a 12 V supply from the fusebox that turns on with the ignition and a 12 V buzzer, you're done. Once you holster the seatbelt, the switch is open and this disables the buzzer.

The weight sensor is usually provided for the co-driver seat.

[DerAlte]

Originally Posted by zipzapzoom

... so technically speaking, if one puts some heavy weight on the passenger seat, the sensor will get activated and the warning will come on. right?? ...

Wrong. Weight sensing seats won't give out a warning if an adult (or a 'large' child) is sitting in the passenger seat. In fact, it won't give any warning if no one is sitting in it.

If the Airbags ECU thinks that someone is sitting in the seat (from this signal) it will fire the passenger airbag when the situation so demands. It won't fire if the signal says 'No one in passenger seat' (there can be a child or an 'underweight' adult in this condition).

In other countries, the driver and sole occupant of the car may need to carry a child in a child seat in a rear-facing position (forbidden to put it in front-facing position) in the passenger seat. In cars without weight-sensing seats, the passenger airbag will fire. To prevent this when carrying a child in the front seat, there is a switch that conveys to the ECU not to fire the airbag.

If your Airbag system is giving a warning, get it checked. Possibly there is an error associated with the weight sensor (wire loose or sensor kaput).

[Tanmay K]

Originally Posted by zipzapzoom

Thanks for info guys,
so technically speaking, if one puts some heavy weight on the passenger seat, the sensor will get activated and the warning will come on. right??
regards

This might depend on the car, I think. The Nissan Sentra in my experience had this quirk of beeping the seatbelt alarm if I left my backpack on the co-driver seat, forcing me to keep it on the rear seat or the floor. IIRC, all other cars I have driven didn't show a warning or sound the seatbelt alarm in such a scenario.

Originally Posted by Gannu_1

If it's just an audible warning through a buzzer that you need, you can get it done by replacing the seatbelt anchor that comes with the normally-closed switch. Connect it to a 12 V supply from the fusebox that turns on with the ignition and a 12 V buzzer, you're done. Once you holster the seatbelt, the switch is open and this disables the buzzer.

The weight sensor is usually provided for the co-driver seat.

This seems very doable. Thanks! I managed to find such a seatbelt anchor on Aliexpress, I'm sure car spare shops might stock these as well.

I tried looking but couldn't locate a weight sensor for the co-driver seat. I suppose the co-driver seat would have to do without the alarm in that case? Still, something is better than nothing.

[Gannu_1]

Originally Posted by Tanmay K

I suppose the co-driver seat would have to do without the alarm in that case? Still, something is better than nothing.

Here's the wiring diagram for the Polo used abroad:



You can see the driver side seatbelt warning is activated by the contact switch (E24) on the seatbelt anchor whereas on the co-driver side, it passes through the seat occupancy sensor (G128) as well.

[fluidicjoy]

The 2020 Polo Vento now comes with a Passenger Side Seat Belt warning as well. The implementation is the classic Contact Strip + Electronic Seat Belt Buckle. It was a pleasant surprise to see this in the Polo since the our particular Tiguan seems to have axed the Passenger Side Seat Belt Warning. The option code is 9P3 = Seat belt reminder, electric contact in buckle.

[vzvish91]

I just brought XL6 Alpha+ MT
Everytime I keep getting these illogical seatbelt warning alerts
Does it require all 6 seatbelts plugged irrespective of whether it's been occupied or not?

[Ravindra M]

Originally Posted by vzvish91

I just brought XL6 Alpha+ MT
Everytime I keep getting these illogical seatbelt warning alerts
Does it require all 6 seatbelts plugged irrespective of whether it's been occupied or not?

I heard Maruti does not have the occupant sensor in the seat due to cost reason. Hence seatbelt need to be plugged in all the time.