airbag help (FAO Cully)

[Niall]

im in the process of fitting some rx8 front seats to my ph3 which means losing the airbags and bringing the light on on the dash. obviously easiest way is to remove the bulb, or get a resistor for the plugs but the rx8 seats have side air bags so i would like to get these working if possible. Im a bit worried about just wiring them up. obviously at best, it will bring the light on. worst, it will blow all the airbags as soon as i start the car.

Does anyone know A) the monitoring and firing resistance of the original air bags and B) same for the rx8 ones or a way to measure them.

Mainly im looking at you cully as your version of auto data seems to have much more information than mine!

[samass]

75 ohms.

[Niall]

75 ohms.

f*ck off! next your going to be telling me 230v is also safe to put through it yeah?

[Jonny b]

Ha ha

[samass]

no, of course not, that'd be retarded. however, 110v would be fine.

[Niall]

jonny you got any input on this being a electrical geek?

[Jonny b]

Never looked at an airbag circuit before,
As you know you can put a resistor inline to turn the light off, as for having them work! Would have to look at both circuit diagrams, can't see there being to much difference to the triggering of them, but the sensors and that? Without looking I wouldn't comment

[Niall]

i know that the sensors wont make a difference. both the rx8 and 306 have single stage deployment so its not really a problem. All im concerned about is the monitoring voltage of the 306 airbag is higher than the firing voltage of the rx8 airbag. cant find a huge amount of info online about them and as you can understand, dont want to put a multimeter across it! luckily, the rx8 ones are under a plastic cover instead of under the cloth so might see if i can get a spare and measure it.....from a long long way away!

[Jonny b]

What info have you got bud?

[Niall]

not much really. All i know is the controller sends out 2 voltages. a monitoring voltage and firing voltage. What these are i really dont know and what resistance the airbag is i also dont know. theres no reason why i cant measure the voltage coming from the controller (i highly doubt even if i put 12v down this, it would set the airbags off. they must have some form of short circuit protection?) but what voltage it requires back i dont know!
tbh im never going to know if it will go off with the 306 controller unless i crash it. problem is, mot testers will be checking factory fitted airbags and these are obviously not factory so dont want to give them an excuse!

[Jonny b]

Let me have a bit of a think when I haven't had a couple of beers, ill get back to you if we knew the values of both systems it would be a peice of piss to replicate

[Niall]

Let me have a bit of a think when I haven't had a couple of beers, ill get back to you if we knew the values of both systems it would be a peice of piss to replicate

yeah. gutted i binned a spare 306 side airbag at the weekend! will do more research but i think cully may have the resistances on auto data

[Jonny b]

The info must be out there as code readers must measure systems in some way to bring up faults

[rocker8742]

Find a spare rx8 seat and turn the voltage up with a variable supply slowly until it blows so you know the triggering voltage?

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From a distance of course not sat on the seat

[Niall]

The info must be out there as code readers must measure systems in some way to bring up faults

yup somewhere! not in any rush but would like the idea of they may go off if someone tbones me instead of just knowing they won't!

[cully]

12v will set an airbag off i have done this on a bench for giggles

the checking circuit measures the resistance of the firing charge this is probably done with a pulsed very low voltage <5v
the firing voltage is probably up to constant 12-35v

measure the voltage that your multimeter reads Ohms @ if it is very low id measure the resistance of the bags and see if they match if they dont you could add resistors to bring the Rx8 seats to the correct value


this is my opinion none is based on fact other than the first line

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The info must be out there as code readers must measure systems in some way to bring up faults

its a little more complexed than you think

the air bags are controled by an ECU so it is all computer controlled
the code readers just read the stored data in the chip not info in any of the bags

[Niall]

yeah ive set airbags off with 12v. problem is though you get these people on other forums saying you can set them off with static if you touch the pins. possible? yeah. Probable? not really but you still worry!

when you say read the voltage my meter reads ohms at, do you mean set it to ohms then use another meter over the lines to see what its producing?

even if i discover the resistance of the airbags, do you still think it will be safe to read the voltage coming from the controller?

[cully]

yes use a second meter to read the voltage of the ohm meter

yes i believe static can set off a bag

if the detonators are the same resistance i would assume they used the same voltage
no i wouldn't read the voltage of the output with a multimeter
i would use an oscilloscope

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oh and the monitoring voltage looks to be 4.6v but unsure if thats current limited

info comming from google
auto data has no info
service box has reams of safe deactivation/ reactavation/ plugging/unplugging info
but no voltages just says use diag equip

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peugeot airbag ecu is looking for 1.6-2ohm for the stearing wheel bag


oh and me spellings getting worse as the beer bottles are emptying

[Jonny b]

This ^^ is why I wouldn't comment without looking at the whole circuit, especially seeing as the pug design is rather old and an rx8 is quite new In comparison

[Niall]

Cheers for your help lads. Tbh I might just wing it and hook it up. What's the worst that can happen right?

[Jonny b]

Awaits thread titled


Airbags hurt

Ha ha

[Niall]

Awaits thread titled


Airbags hurt

Ha ha

haha yeah tbh i think ill plug it in sitting in the back seat. cant hit me then lol.

what size resistor is needed to get rid of the light anyway? just incase i get bored of trying to work out if i can connect it up and just leave it as is?

[Kwik]

lmfao! they do oh they do

[Niall]

lmfao! they do oh they do

really? ok ill extend the wiring to behind the garden wall and do it there! haha

[Kwik]

i accidently let off one think it was a vauxhall one and it made me blacker and tenderrer around my face. so now i always disconnect power and don't mess with them when they live lol

[Niall]

i accidently let off one think it was a vauxhall one and it made me blacker and tenderrer around my face. so now i always disconnect power and don't mess with them when they live lol

yeah ive set them off before and they are quite scary tbh. See some of the damage they can do even when people are wearing a belt in a crash

[Kwik]

[vincent1]

might be worth a read
http://www.ebay.co.uk/itm/1-8-ohm-resist...__________

[ash240970]

What about going on the RX8 forum and asking on there as you may find some people have put buckets in or have access to technical data.

[Niall]

What about going on the RX8 forum and asking on there as you may find some people have put buckets in or have access to technical data.

just done it. lets see how much of a friendly bunch they are!