Mine came on while driving back after collecting the car.

It happened when I moved the seat right back and down, so could be something wiring related under the seat. It stayed on for the entire journey even though I moved the seat back to normal. Hasn’t happened again. There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
Fiat 500x 1.4 multiair Lounge 2015
2010 LR D4 Commercial 2.7 TDV6

This fault seems to plague a lot of 405s.
Driving home from Scotland yesterday after a faultless 1500 mile tour of “Nichola’s Fifedom” the Airbag light came on going around the last roundabout before home. I was still in motorway driving mode so we were pulling a bit of lateral G on the turn and “bang” light on. When home tried a reset using the IID but but no luck
Searched the Forum and got lots of help. As advised I moved the seats over their full range and rummaged around underneath tugging and pushing all the connectors I could reach.
Did a reset light out and all seems to be well.
Fingers crossed and thanks to the Forum.

I'm currently looking for a fix for this.
Light comes on after I've lowered rear seats like others have experienced.

I'm looking for a picture or diagram of the under side of the passenger seat as I can't see much of the wiring when I try and see under it.

I'll keep looking unless someone has a link handy or better search terms than I'm obviously using

Love this forum, best on the web

Mine's done this twice over the last four years of my ownership (the first time when I'd only had it a week). I was told that most commonly it's the connector under the driver's seat, which slightly loosens. A quick fiddle under the seat pressing the two sides of the connector together again seemed to work. I switched off the automatic seat backwards movement upon ignition off which did the job until last week when it happened again. Once more a fiddle with the loom worked. Clearly a common problem which JLR should have sorted out. Looking back through my paperwork, the first two owners of my vehicle had the loom replaced twice under warranty, firstly in 2014 and again in late 2015.

SRS connections have gold plated pins, the problem is they are susceptible to contact fretting having a relatively soft contact surface, this is exacerbated by having the harness unrestrained within a short distance of the connector housing.
There are two possible fixes - one is to use cable ties to remove any tension from the harness before it enters the connector housings, this will also reduce the chances of harmonic resonance increasing the contact fretting - and therefore transient increases in contact resistance (which is what causes the SRS warning), the other fix is to fill both halves of the connector housing with a dielectric grease, LR use Nyogel 760G as a workshop item, as well as preventing contaminants on the contacts it does a good job of damping any movement of the connectors in the housings, effectively minimising the chances of resistance changes due to movement.
Personally, I'd use cable ties and Nyogel

I can't visualise the setup on the rear seats - it's been a while, but there are two possibilities - either the harness on the moving element is too tight and is pulling the pins in the connector housing or the harness is chafing on a metal component in the seat and grounding one or both wires in the harness. Either way, remove the stress and re-insulate the conductors if required, and the concern will go away. It may be an idea to unlatch the connector housing from it's bracket so it has free movement, it might look a bit untidy but it should solve the issue.

See this thread for images of the underside of the seat...

https://www.fullfatrr.com/forum/topic55605.html

I disconnected the battery, then gave all three connectors a good squirt with electrical contact cleaner. In addtion, I removed some of tension on the cable harness by removig a little of the fabric tape from the loom. No problem since. Kev

2014 L405 RR Vogue SE 4.4 SDV8 in Corris Grey
2010 L320 RRS HSE 3.0 TDV6 in Stornoway Grey

Yep, that C33 B1/B2 looks like there should be another 10mm or so of wiring and some sort of strain relief, TBH, most connectors are only there for the convenience of the assembly line, if it were mine, I'd snip it out and solder a bit of wire in it's place. and run a stiffener across the joints to prevent any stress on the solder.

Apologies for late reply,
Thank you for the advice and links, much appreciated. I'll get on with trying to resolve.

We took two dogs to the vet tonight. I removed the parcel shelf and put it on the back seat. When we set off I noticed the airbag light stayed on 🤬

Am I right in the thinking it could be the parcel shelf on the back seat?

I know I can move it tomorrow and I’ll find out, I just thought it might be useful for others 🤷‍♂️😉

When my airbag light came on, following advice from fellow members, check wiring under passenger seat, don't unplug anything but check all connectors are pushed home.

Thanks

I'll try that first as its not gone out!

Mine appears to be under the drivers seat. I adjusted the seat today and the light went out!

Had mine come on a couple of times and moving the seat around chases it away for a while. Maybe a permanent fix is to loosen the seat, tilt it back and get to the connectors to do a proper job. Probably wise to disconnect the battery first to avoid an unwelcome airbag appearance.

I’m unsure why they all fail in a similar fashion… Not like it’s vital now is it… 🙄😜

Poor design. This happens so much with all manufacturers and we’re left to pay for it.