Jimny SRS details: airbags, seatbelt pretensioners

One of the big changes brought about with the generation 4 Jimny is the addition of a number of supplemental restraint system (SRS) features. While some (most?) gen3 Jimnys had one or two airbags, gen4 Jimnys can have up to 10 and also feature seatbelt pretensioner devices. There’s always some questions related to this, even if indirectly (e.g. ‘what seat covers should I get’) so I wanted to try to lay out some facts.

Note that some markets get fewer airbags than others. I don’t really want to go into these differences

Sections


SRS features

There are two main supplementary restraint system (SRS) components in the generation 4 Jimnys: airbags, and active seatbelt pretensioners.

Airbag graphic from the Suzuki New Zealand brochure for the 3 door Jimny. Note that drivers side curtain airbag is not depicted as it would obscure the view of the other 5 airbags in the car.

You can get a good overview of just how many airbags there are and what they protect from the ANCAP test results.

The seatbelt pretensioners are harder to image in use; their function is to provide tension on the belt if an accident is detected, holding the driver and any passengers more in place. The seat belts also have a limiter function so they won’t hold you too tight, either.

This is from US Patent US7124974B2 which illustrates how a pyrotechnic pretensioner installed at the seat belt reel works. Left is before deployment, right is after deployment. A small explosive charge (part 12) generates a pressurised gas (#14 in the right diagram), which then pushes some balls around to engage a cog. This cog, in turn, tightens the seat belt removing slack from it.

Below I’ll go into a bit more detail about the Jimny’s SRS arrangement. Note that this syste,, like many cars, deploy mostly from force sensors rather than a simple impact switch and there’s a lot of smarts that go into the deployment timing that I’m not privvy to.

Seat airbags

A primary component of the Jimny’s side impact protection for drivers is the provision of airbags inside the front seats themselves. These deploy from the outside bolster of each front seat as needed (generally from side impacts).

Photo originally from a Gumtree listing by SA Auto Spares for a wrecking vehicle: https://www.gumtree.com.au/s-ad/1314448876

There are some considerations around this seam that opens up when the airbag deploys if you are going to fit seat covers to your car. Other than that not really any considerations other than if you’re going to remove the seats for interior work, or, you want to look at changing seats.

Main driver and passenger airbags

These are the obvious airbags to most people (and what they’ve come to expect from a car). These airbags deploy from the centre of the steering wheel for the driver and from the large part of the dashboard.

Here’s a quick before and after I found via the ol’ ‘gram.

Pics from @airbag_overhauling on instagram: https://www.instagram.com/airbag_overhauling/p/Cyv3Tatr795

Interestingly, the steering wheel airbag comes out in a way where the Suzuki logo is not disturbed but instead breaks the centre cap in a sort of ⅔ / ⅓ sort of a way.

Pic from @airbag_overhauling on instagram: https://www.instagram.com/airbag_overhauling/p/Cyv3Tatr795/?img_index=3

Not much else to say about these, really! Do be careful of the steering wheel centre airbag if you’re pulling the steering wheel off, and, be considerate of the air bag for the passenger if you fit a dash mat or dashboard accessories.

Curtain airbags

There are a couple of additional airbags in the car, being curtain airbags that deploy from the ceiling. They run the full length of the car, from the front to the back, and deploy even if there’s no-one in a rear seat on the side they need to deploy on.

Seatbelt pretensioner system


Common questions

‘I want to get seat covers, what do I need to think about?’

‘I want some roof height storage’

‘I’m removing my rear seats, what do I do about the seatbelts?’

‘I’m fiddling with something related to the airbags, what should I think about first?’

‘I’m installing a dash mat, do I have to worry about airbags?’

‘I want to install different seats’