Hello,
The airbag light on our car doesn’t come on with the ignition, is it true that the ecu would normally mske a buzzing sound if the bulb blows or is removed??
There doesn’t appear to be a fuse for the ecu, it looks all connected from what I can see, as its buried up in the dash, I was going to remove the instruments and check the bulb…
Can you do diagnostics for the airbag from the connector under the hood, to see if the bulb works??
Cheers,
Mark
The airbag light should illuminate with ignition on,even if there is a fault in the system.Looks like the lamp circuit may have been tampered with.It is possible to activate the self diagnostic system from the engine bay circuit,but the light needs to be in working order.
Hello,
I’ll try and get in there today and check the bulb etc, all the wiring looks in good nick…
I did wonder if the airbag at some point developed a fault, and bulb has given up the ghost from being on so long.
My only questioning for the buzzing sound has come from me reading so many posts from internet searches that mention it, its the first time I’ve ever come across something like that to be honest if it does…
If I find anything I’ll let you all know,
Cheers,
Mark
well it turns out that the bulb has been removed!!
I’ve swapped it fr another one and the bulb stays permanently on with the ignition on…
Can anyone please advise what pins to short on the diagnostic connector to make it flash a fault code??
Thanks again,
Mark
Have a look in the Downloads section, all the information on airbag flash codes is there.
The reason for removing the bulb will likely be that the airbag module has failed and the airbag system has been decommissioned.
I would expect the airbag steering wheel to have been replaced though to stop MOT questions?
If I am correct, it will be very expensive, if not impossible to recommission the original airbag system, so remove the bulb and forget it. Hopefully the next MOT technician will not pick up the fact that the car should have a working airbag system.
Well yeh probably the best thing to do in all fairness, not sure how the airbag would perform after 22 years anyway…
The original wheel with airbag is still there, looking back on past MOTs there’s no mention of it, amongst other things… Maybe a little eBay purchase is in order…
Cheers,
Mark
A quick look at the MOT tester’s manual shows that:
Airbags fitted as original equipment must be present. (So, removing an OE airbag is strictly an MOT fail.)
The airbag malfunction indicator light does not indicate a malfunction.
It appears at some time the bulb has been removed to ‘hide’ a defective airbag system. It’s not specific, but I would expect the tester to look for the light to illuminate and then go out to confirm the system is fault free.
It’s odd that it hasn’t been picked up in the MOT tests.
JS
Agreed but most MK1 cars do not have this feature. As far as I know it was only fitted to a small number of later 1.8 MK1 cars. Given the scarcity/age of replacement parts, repair/recommission not feasible - removing evidence of the airbag system has to be the sensible way forward.
Dash has to be removed to get to module so leave alone - I would remove bulb and change steering wheel.
Hopefully this is enough to get the car through an MOT without a tester who happens to be an expert on MX5s forcing it off the road
For the Mot,the warning light must illuminate and go out after a few seconds .The anomaly of the system is that if the light does not illuminate at all ,then this is an advisory,not a fail.
Thanks guys,
From what I can make out the light will flash a code constantly if there is a problem, if its on solid then it points to the ecu or power loss.
If it wasn’t such a pita to get to I’d have it apart and check it out, historically they had a bunch of electrolytic capacitors inside that would trigger the airbag in the event of power loss in an accident, these will eventually give up and cause all sorts of problems.
I’m guessing from rhino666’s post the dash is best left alone!
The guy who prepared it has been the cars mot tester for the last few years, along with another guy at the garage, and to be fair has been quite strict with it judging from past mots.
So its going back together without the bulb for the foreseeable… maybe a steering wheel swap, the non airbag ones look better anyway, my brother and another guy both run Nissan Sylvia’s tuned and have removed the original steering wheel and have had no worries at mot time… so we’ll see how it goes, cross that bridge when we come to it…
Thanks again,
Mark
Just out of interest, I just found this, from June 2014:
Where passenger air bags are present it is also often possible to disarm them, or they may automatically disarm where there is little or no weight on the passenger seat. This may be accompanied by a lamp permanently on to highlight the airbag has been disarmed, this is not considered a SRS MIL, and therefore isn’t a reason for rejection.
Cheers,
Mark
Don’t let me discourage you from taking your dash out if you want to play with the module.
It is the sort of thing I would do. Bear in mind that removing the dash sufficient to facilitate removal/inspection on this module is likely to take at least three hours.
I have just taken a MK2 module apart. There are a lot of very small surface mounted components but also several large capacitors. These usually show damage so you could be on to something. The MK1 module is a different part but likely similar components.
Thats interesting to know you’ve seen grotty capacitors in there, if I ever get the inclination to have the dash apart I’ll be sure to have a go at it.
I’m just a bit of a stickler that if its on there I want it to work, if you know what I mean…
Is it accessible if the front panel is removed, with the heater controls etc, it looks pretty high up to me??
A customer of mine had a replacement fitted by a garage who charged 4 hours labour. On that basis I was suggesting that you or I would probably take 3 hours to remove the dash. As I understand it there are no shortcuts but someone else who has done this before may be able to comment further.
Think I was a little unclear when talking about the capacitors. I was talking generally of visible signs of damage where the top starts to expand and split at the seams. Not seen this damage on the airbag module I took apart but perfectly feasible that it would occur after 20+ years.
Just a quick note to the end of this thread for anyone that’s interested.
I took our Suzuki for its annual MOT yesterday, and whilst there I got the testers opinion on the airbag light situation.
His advise was on a vehicle of that age he wouldn’t worry if the system was decommissioned and the light doesn’t come on with the ignition, but would certainly pull it up if the light stayed on.
I the system has been taken out of commission he advised just to make sure the airbag or control unit is disconnected to avoid the possibility of the airbag going off falsely, or to swap the steering wheel for a non airbag one.
I think his overall opinion was that he’d be dubious of the integrity of it all anyway after 22 years and wouldn’t guarantee its reliability anyway…
Seeing the hydraulics on their ramp maul the suspension around gives me the willy’s… if it isn’t buggered it will be in a minute!!!
He is right ,apart from you should be issued with an advisory for no airbag light showing
As he said thou I would put a non airbag wheel in as theres no evidence of the airbag system ever being there especially on a car of that vintage.
He probably will, it was the Suzuki that was in yesterday…
Hi
Yes i gathered that
he was the one dishing out info so he should also mention you would have an advisory too
thats all i was saying