am shopping for an early 300 Tdi discovery at the moment. as you all know they come in many different spec levels, some of which feature driver and sometimes passenger airbags.
whats the score with fitting a winch bumper to an airbag equipped vehicle? is it a non-starter?
are airbags (if fitted) part of the MOT test?
and if i have a bit of a shunt and the airbags deploy, will the insurance company write it off, just because of the cost of the airbags?

and finally, should i avoid older cars, just because they have an airbag, or should i not worry about it... i know they are a great safety fearture, just not entirely sure they'd suit my purpose...?

thanks in advance

m@tt.

As I understand it you should only really fit a bumper that has been crashed tested with airbags. Which is probably none of them so I guess most will ignore that.

MOT don't know but I bet if there's a warning light it'll fail. You can't "test" an airbag without detonating it hence the requirement to replace them every 10 years.

Write off - probably, airbags are £1000 odd a side on older vehicles. A bit like ECUs on older vehicles, if they require replacing it could effectively make the vehicle uneconomic to repair.

ARB do an airbag bumper; it has replacable crush sections.

The other thing to remember is, in an accident, an airbag may well save your life. The write off thing is an issue but if you can get salvage retention of the vehicle its less problem as you can remove all the expensive bits.

do they need replacing every 10 years?
is that a legal requirement? if so the 1995 disco i'm going to look at on saturday might need two new airbags?

I also read somewhere that if the air bags go off you have to replace the entire airbag wiring loom as well. Which makes it even more expensive. If the bags go off or fail on mine then I'll just remove them, take the bulb out and find the relevant non airbag bits to put the dash back together.

Ivan

yeah, that was my train of thought, but i'm not sure if that would invalidate your insurance... but then again, its only modifying it to standard, 'non-airbag' spec......

This is a myth. Discovery and RR SRS systems use motion sensors and an ECU. Two sensor at front measuring front to rear acceleration and deceleration and one in the centre measuring side to side acceleration and deceleration. The only affect of fitting a HD winch bumper is that you are likely to increase the deceleration rate slightly as there is less absorption of energy over a stock bumper. This therotically could set of the air bag sooner than a stock bumper.

In practice, by which I mean hitting a tread head on while coming down a hill at a fair rate of knots in a P38A , it must take a fair impact to set the airbag off

Cheers

Steve

I have a 1995 Disco and when I asked my LR dealer for a quote for replacing them at the 10 year mark I fell off my chair.

Something like £2900 including labour and VAT.

"No thank-you" was my response.

http://forums.lr4x4.com/index.php?showtopic=302&hl=

ok, thanks guys, so i can fit a HD steel bumper, and as far as the '10 year rule' goes, i guess i can just ignor it?????
hmmm..... any other helpfull hints would be most appreciated...

Steve,

It's not a myth as such - Land Rover themselves don't approve fitting of anything on the front that hasn't been crash tested with airbags, it certainly applies to bull bars so I expect it does to bumpers too. Doesn't mean the airbags won't work - just means that they aren't certified to so I imagine insurance companies might take a dim view - but if they are OK with it then fine. It is all to do with the rate of crumple versus the deceleration characteristics that trip the sensors, I think. I've seen some pretty massive accidents where the bags have not tripped so I think they must genuinely only detonate in a hard frontal impact, I've seen a couple of vehicles that have rolled several times after coming off a road at speed and the bags haven't gone off!

A Discovery of that age will use one of the two systems:

- Multi point sensing which is two impact sensors at the front and inertia sensor in the ECU - this is what my 1996MY Disco had so probably most likely - on these you need to trip one of the front sensors and the ECU sensor simultaneously, IIRC, to get a face full of bag

- Single point sensing which is in later Discovery 1s, just the airbag ECU sensor

Don't know about later vehicles, I just read up on it when I got my last Disco as I was worried about setting them off when off road.

The reason they need replacing every ten years is that is the life of the airbag propellant (sodium hydrazine?? something like that) after 10yrs you cannot guarantee it will detonate on command because the juice goes stale, the only way to test it is to detonate it, and then of course the airbag is F'ed anyway and needs replacement! I don't know what view UK insurance companies and MOTs are taking on this now that it must be a serious issue with older vehicles coming to that age - but I guess most people aren't going to fork out the stupid amount of money required to change 2 of them, less so when it becomes 5 or 8 or 12 bags in a few years time..... I did hear somewhere a while back that LR had backed off a bit on the 10 year rule because it might come back and bite them with the vehicles being worthless if the rule was enforced, but I'm afraid I don't know the current score.

You can convert the vehicle to non airbag in a D1 because the correct bits are available, but of course most later vehicles like the D2, D3, etc only have airbag steering wheels and to fit an aftermarket wheel and dump the bag may mean type approval is invalidated which might give insurance/MOT problems? don't know but I bet the insurers would find it a convenient excuse to wriggle out of something!

I think you would be right on this Stephen.

The premium calculation will be based on the risk to driver and passengers which will be reduced in a a vehicle with airbags. Remove them by all means but before doing so at the very least let your insurers what you intend doing - unfortunately at this point they are likey to say they are not willing to cover the vehicle.

Reading this actually has just reinforced the need for me to think about a new vehicle - my current steed has a total of 8 airbags and if all those go off (and I haven't suffocated in the process) I'll need a second mortgage to replace them!!

Can just see it now

skreeeeeeeeeeeeeeeeeeeeeeeeeeeechthumpBANGBANGBANGBANGBANGBANGBANGBANG

mmmph mmm mmmpph hlp mmmmph mmmph urk

Later on the bit of paper says

"Cause of death: Asphyxiation by multiple airbags"

But seriously I hate to think how much it would cost to replace 8 x Toyota airbags, we all know how much Toyota bits cost just for oil filters and stuff

thanks Bogmonster, interesting stuff.
i guess i just dont want to buy a motor that'll need over half its value spending on it in the next year or so, just to bring the airbags up to date........

i think i'll be doing a little more research on this, so if anyone has anything else to contribute feel free......

I've an idea (but I'm not certain, so check this out properly) that if a vehicle was originally equipped with airbags it must have them in working order for the MOT. I think working order essentially just means that the warning light does all the things the manual says it should (so just disconnecting it probably isn't good enough).

Hopefully I'm wrong and the MOT rules just say they must appear to be working if fitted

By the way - if you do take the air bags out of a vehicle, disconnect the battery for some time before you do it (at least an hour, I think - again, I'm not sure how long it takes to electrically discharge them, so check). You do not want an air bag going off six inches from your face... Once you've removed them you must set them off before you can legally dispose of them, for fairly obvious safety reasons. Time for some fun with a couple of long wires and a car battery, I guess

I think the book says 10 or 15 minutes to discharge the airbag system capacitors but I usually give it half an hour to be sure...

No idea how to set one off, you can get proper things but I don't know what voltage is needed. I guess if you plug them into an electric fence energiser the 8000 volts coming out of that ought to do the trick

Since you seem to be in the know about this MJG. I looked at buying a softdash RRC a while back and doing this thinking logically that the insurance could not be any more than a year earlier RRC without them.

I was sadly mistaken when I enquired, guess logic really doesn't come into insurance companies lexicon, perhaps a smaller company with real people who are not based in Mumbai might be prepared to talk directly but I never went that far.