Technical Airbag sensor warning

[siwilks200]

Hello my airbag sensor warning goes off everytime I turn on the ignition or engine and I have two error codes that come up on a diagnostic reader at the garage.

1. Driver's side airbag explosive charge 2nd stage.

2. Drivers airbag squib

About a year ago I removed my steering wheel and airbag to replace the indicator module, I've had no problems until recently!

The clock spring is something to look at but I don't know what the above two warnings are about

Any help is much appreciated

 

[Artermis]

From experience I'd say the airbag ECU has detected an open circuit, i.e. no connection or really high resistance, thrown an error and given you a light to look at.


It's highly, highly unlikely that the airbag has decided to die all on its own for no reason, it just doesn't happen. They're stupidly simplistic bits of kit. Essentially a little ignitor coupled to a small explosive that when set off fills a bag with gas. All an explosion is by definition is a rapid expansion of gases.


If you're really unlucky it might be the airbag ECU has gotten damaged, either heat or moisture, a dry join, failed POT or something and gone bad. I've known that happen.


More likely is a poor connection. Given how easy they are to disassemble, pop the bag off and check the connections on the clock spring and the bag itself. Give them a spray with some contact cleaner and reassemble.


I'm not sure off top of my head what system Fiat uses in the Stilo, it'll likely be either the MY97 or MY99. Probably the later 99 by this point actually, 97 is like pre-2000 I think.


Its been a while so I can't remember off the top of my head. One of the systems will 'clear' itself, the other won't. So don't be immediately surprised if the light doesn't go out my itself. I think it should but it's been a while since I'd had to deal with one. If it won't clear itself it'll require reset by diag software. MultiECUScan will do this but you need to connect to the correct pin on the diag OBD port. I assume you've got this covered as you're aware of your fault codes.


They usually scan themselves on boot, i.e. ignition on, so if it's going to go off it'll probably happen a few seconds after you turn it on and start the engine. If it doesn't go out after 10 seconds, it won't go out.


Disclaimer time - work with airbags is playing with explosives and care is required. Frankly, I've work on airbags with batteries connected, ignitions on and even engines running before now; you'll struggle like hell to set one off but if you do you'll regret it.


Play it safe and have the battery off whilst you tinker.

 

[siwilks200]

Thanks mate for the very detailed reply

I got the Garage to use their diagnostics tool and they cleared a couple of codes but two which are posted above remain.

I don't know if we can get rid of them as they are always there so I think something needs fixing.

I've been told cleaning the connections under the passenger and driver's seat should be cleaned with contact cleaner which I have done but to no avail.

The contacts onto the back of the airbag are connected fine but I will clean the next.

The clocks spring seems to be a bit rattly so perhaps it's rotated incorrectly. I do not know how to get it back into the right position...is there a guide for this?

I am considering replacing the complete indicator stalk first as this would come with anew clock spring as well ad the fact the indicator is now not holding down to the left turn position when I push it down... it just pops back up which is frustrating!

Where is the ABS ECU for me to clean those connections?

Cheers bud

 

[Davren]

Where is the ABS ECU for me to clean those connections?

The ABS ECU is below the ABS modulator located behind the battery tray.

However, I suspect you mean the airbag ECU, which is located under the heater casing.
.

 

[siwilks200]

Oops yeh the airbag ecu! Thanks

I've had experience changing my heater blower a number of times....Guh.....so I will get upside-down and back to front and stick my head in the footwell for an hour to contact clean those ecu connections in the last two photos?

If that doesn't work is it easy to remove so I can get a second hand one?

TA

 

[siwilks200]

Well I've cleaned all the connections and it hasn't changed anything

what would you recommend next?

 

[siwilks200]

HI Davren, i have now changed the airbag ECU but no change unfortunately.

Apparently the guy i bought the ECU off said he fixed his by unplugging it all turning on the ignition, replugging it all, turning it back on and clearing the codes - and it seemed to reset it

for me this didnt work but my OBD2 device wont recognise the airbag codes to clear!?

Any ideas? thanks

 

[Ralf S.]

About a year ago I removed my steering wheel and airbag to replace the indicator module, I've had no problems until recently!

The clock spring is something to look at but I don't know what the above two warnings are about

Any help is much appreciated

Just quickly off topic ..

Is it simple to remove the airbag, wheel and then the indicator stalk assembly? I'm going to swap my indicator (lights?) module to see if it fixes a headlamp high-beam problem which is proving illusive. Is there anything particularly tricky about it?

What's the clock spring? Will it fly out if I remove any of these ^ parts?


Ta.


Ralf S.

 

[Artermis]

Just quickly off topic ..

Is it simple to remove the airbag, wheel and then the indicator stalk assembly? I'm going to swap my indicator (lights?) module to see if it fixes a headlamp high-beam problem which is proving illusive. Is there anything particularly tricky about it?

What's the clock spring? Will it fly out if I remove any of these ^ parts?


Ta.


Ralf S.

Ralf - real easy. Airbag should unscrew from rear and lift out. Follow the steering wheel removal guide mate.


The clock spring is the connector between the wheel and the rest of the car, it allows for the rotation of the movement without causing brakes in connections. It might have a steering angle sensor and other bits in there too.


Don't rotate the clock spring!! have some sticky tape on hand to fix it in place, otherwise your indicators won't cancel like normal as it'll get out of sync or angle sensors will go bonkers - and they're bad enough on Italian cars at best of times!

 

[Ralf S.]

I discovered the clock spring....

As you say, it looks like it's just itching to escape.. but I worked out it has two tabs at the back that fit into slots on the piece behind it (on the indicator/wipers module) that affect where two more tabs are (that actually cancel the indicators).

The two "cancelling" tabs go at 240 and 300 degrees .. then the clock spring lines up if you make sure the connector block for the airbag is at the bottom (180 degrees).

Thanks for the advice though.. I wasn't sure quite what to expect in there (first "airbag" wheel I've tinkered with.



Ralf S.

 

[siwilks200]

.. but I worked out it has two tabs at the back that fit into slots on the piece behind it (on the indicator/wipers module) that affect where two more tabs are (that actually cancel the indicators).

The two "cancelling" tabs go at 240 and 300 degrees .. then the clock spring lines up if you make sure the connector block for the airbag is at the bottom (180 degrees).

Hi. My airbag and horn both weren't working beforehand hence why i was looking at my set up. Months ago i changed the indicator stalk (inc clockspring) to fix an indicator issue which worked fine....everything did...months later whilst doing work on the EGR valve and brakes the airbag and horn suddenly didn't work.

I've cleaned all the connections, cleared codes (2 wont budge) and changed the airbag ECU - none have worked. So renewing the indicator stalk with a new clockspring is next (seeing as i have definitely played with it whilst cleaning connections - nob!) now i have defo mangled it proper as i heard it crunching while turning the wheel once.