Last year my Stilo 1.2 had the dreaded passenger seat occupant sensor problem, causing an airbag warning light.

I bought a little device from eBay and that did the trick.

Since the warning light has returned (apparently, it came back on after someone drove the car over a hard bump).

I've unplugged, cleaned and jiggled the airbag connectors under the two front seats. I found two that look similar in the boot behind the pockets in the boot above the rear wheels, and another behind a panel in the lower glovebox, and I've done the same with them.

Of course I have no idea which of these airbags is causing the problem; for all I know the little device I installed has failed.

Do you know anyone who'd have the equipment to hook the car up to a diagnostic computer to get a report for me, for a few pounds (in or near Cardiff)? I presume it doesn't take too long.

Thanks.

Evening

For £20 quid or maybe less (only done a quick search on ebay) you can get a ELM327 usb cable plugs into your car, and using the FREE Multiscan software you can scan for fault codes and much more.

i have used mine loads of times and saved £££'s.

I have this one (might find a cheaper price)
http://www.ebay.co.uk/itm/MULTI-ECU...iagnostic_Tools_Equipment&hash=item4176d0c0ac

And Multiscan software and all the info you need about cables etc
http://www.multiecuscan.net/

Could well be the simulator has thrown the towel in!.

Paul

paullawton2007 said:

Evening

For £20 quid or maybe less (only done a quick search on ebay) you can get a ELM327 usb cable plugs into your car, and using the FREE Multiscan software you can scan for fault codes and much more.
Paul

Click to expand...

Thanks for all that information. Now the challenge is to find someone with a computer running Windows!

Or, any idea if the software is likely to work on a Macintosh or Linux machine running virtualised Windows?

hhmm im not to sure on mac. i use all my work software on a xp virtual machine that has com ports etc. so couldnt see why not.

try a search on here im sure i have read something.

https://www.fiatforum.com/stilo/216751-fiatecuscan-diagnostic-software-11.html sure it would of been covered here. id have a look for you but the babies kicking off!

paullawton2007 said:

Evening
For £20 quid or maybe less (only done a quick search on ebay) you can get a ELM327 usb cable plugs into your car, and using the FREE Multiscan software you can scan for fault codes and much more.

i have used mine loads of times and saved £££'s.
Paul

Click to expand...

I think I am going to have to get this, but can you confirm whether it's all I need for my Stilo (1.2, 2002)? The item you linked to says "A KKL VAG COM cable may also be required for certain ECUs" but how would I find out whether this applies to me?

Thanks!

http://www.multiecuscan.net/SupportedVehiclesList.aspx

scroll down to the Stilo 1.2

the ECUs labelled in black are available in the 'Free' version, the ECUs labelled in red are available after you purchase it.

if you want FULL connectivity to your ECUs get yourself an 'ELM327 v1.3/1.4' and a 'Vagcom' cable.

you will see KL, KL1, KL3, KL9 & KL12 mentioned for various ECUs... this company do the relevant 'patch' cables for full ECU connectivity. the purple lead isn't needed for the stilos but the £18 theyre asking for this set is CHEAP. the yellow lead alone from them is £10.

oh and you'll need a copy of windows if it comforts you, im currently trying to get all my fiat related software to run on Fedora, but its a game and a half... it'd be much easier to find yourself a copy of windows and run a dual boot. trust me ive tried!

ECU Error code interpretation (front passenger airbags)

I have the airbag warning light on the dashboard.

I ordered an interface and a set of adaptor cables which arrived today, so I borrowed a Windows laptop from work, downloaded the Multiecuscan software and connected it all up.

The errors:

32 Front passenger weight sensor Unknown/Internal error
32 Front passenger weight sensor Open circuit/short circuit +V batt

So: I have already bypassed the sensor with a mat emulator device, which did the trick for a bit last year.

Does this suggest that the device is not working? Or that there's a problem with the wiring somewhere else along the line?

Many thanks!

Re: ECU Error code interpretation (front passenger airbags)

EvilDMP said:

I have the airbag warning light on the dashboard.

I ordered an interface and a set of adaptor cables which arrived today, so I borrowed a Windows laptop from work, downloaded the Multiecuscan software and connected it all up.

The errors:

32 Front passenger weight sensor Unknown/Internal error
32 Front passenger weight sensor Open circuit/short circuit +V batt

So: I have already bypassed the sensor with a mat emulator device, which did the trick for a bit last year.

Does this suggest that the device is not working? Or that there's a problem with the wiring somewhere else along the line?

Many thanks!

Click to expand...

could be both, find someone whos got ab light on and test device. if it doesnt work for him chances are that device died.

Re: ECU Error code interpretation (front passenger airbags)

Well, another test this morning and it seems that whether or not the mat emulator is in place, the system thinks that the front seat passenger is present.

Re: ECU Error code interpretation (front passenger airbags)

I am still fighting with this wretched thing.

If the seat is plugged in, in the normal way, the error I get is:

32 Front passenger weight sensor Unknown/Internal error

If I plug in the mat emulator (the OCS emulator device) I also get an additional message:

32 Front passenger weight sensor Open circuit/short circuit +V batt

Does this suggest a problem with the wiring, or with the device?

And again, if there's anyone in or near Cardiff who'd be willing to let me check this device by plugging it into their car, I'd be immensely grateful!

Thanks!

dont know how i missed this the first time round... sorry EvilDMP

the internal errors relate to the actual 'brain' of the mat/emulator if you have this fault the mat/emulator is dead. basically the ECU cant make sense of the signal coming back from the mat/emulator (if theres a signal coming back at all).

the extra fault to do with open/short is most probably the issue with the emulator, because its not powering up it will throw the 'internal fault' message too... where did you get it from? i had similar issues with mine and i got replaced FOC as it was soo soon after i purchased it from http://airbaglightoff.eu/fiat-stilo...sx29-occupant-classification--sensor-76-p.asp

if you want to check the wiring...

check continuity from Pin19 of the Airbag ECU to Pin2 of the OCS Plug (chassis side) this will confirm the 'signal wire' is good.

check for a +V Batt at Pin 1 of the OCS plug (chassis side) its fed from Fuse 50 (7.5amp mini blade)

check continuity between Pin 3 of the OCS plug (chassis side) to Gnd

if all these check out the chances of the ECU going down JUST for this circuit are neigh on impossible and F50 also feeds the airbag ECU itself and is branched off to the OCS.

heres the wiring diagram for it anyway... your looking at B2(under dash fuse board), M60 (Airbag ECU) and K65 (OCS Mat/emulator)

richydraper said:

dont know how i missed this the first time round... sorry EvilDMP

the internal errors relate to the actual 'brain' of the mat/emulator if you have this fault the mat/emulator is dead. basically the ECU cant make sense of the signal coming back from the mat/emulator (if theres a signal coming back at all).

Click to expand...

The emulator has a little LED on it that says "OK" - sometimes steady, sometimes flashing (flashing sometimes when I have been plugging and unplugging things all over the place, but usually steady).

What signal is the airbag ECU expecting from this device? A steady DC voltage?

the extra fault to do with open/short is most probably the issue with the emulator, because its not powering up it will throw the 'internal fault' message too... where did you get it from? i had similar issues with mine and i got replaced FOC as it was soo soon after i purchased it from http://airbaglightoff.eu/fiat-stilo...sx29-occupant-classification--sensor-76-p.asp

Click to expand...

I think mine was from http://www.ebay.co.uk/usr/b.l-shop47?_trksid=p2047675.l2559

if you want to check the wiring...

check continuity from Pin19 of the Airbag ECU to Pin2 of the OCS Plug (chassis side) this will confirm the 'signal wire' is good.

Click to expand...

I certainly do! I'll have a go at that tomorrow. One question: how do I get at the airbag ECU? I understand it's in front of the gear lever and below the heating controls, but it looks like a devil to get to.

Huge thanks for the detailed information.

the status light is showing that there is atleast power getting to it... but if theres any kind of fault on the circuit board then you could end up with all sorts of spurious faults. the indicator light, i dont think will be a definative indication of the boxs integrity.

i have never actually figured out what signal the ECU should recieve, the OCS mat is effectively just a big variable resistor, but it has some kind of logic device attached to it, it relays info not only about seat occupation but where abouts on the seat the weight is distributed. this allows the ecu to calculate firing sequences for the dual stage airbag in the passenger side of the dash. the Emulator mimics whatever this signal may be and shows the ECU that the passenger seat is always occupied. its not as simple as a simple resistance value, feeding or grounding the signal pin, else we wouldnt need the emulators

if you remove the drivers side footwell trim panel that sits on the center console... its where the GREEN CIRCLE is in this picture


check your wiring and if that checks out ok i would be seriously questioning your OCS Emulator. maybe return it if you havent had it that long or buy another. my emulator indicated it was ok but something had happened to the chip inside and it wasnt sending the correct info to the ECU.

richydraper said:

check your wiring and if that checks out ok i would be seriously questioning your OCS Emulator. maybe return it if you havent had it that long or buy another. my emulator indicated it was ok but something had happened to the chip inside and it wasnt sending the correct info to the ECU.

Click to expand...

The 12V from the fusebox to the OCS emulator, and the connection to ground are good.

I can't trace the signal connection from the OCS emulator to the Airbag ECU.

I have unplugged two multiple-pin connectors with green levers from it; one has 22 pins the other 24. I assume there aren't others!

I can find continuity to ground connection on these, but not to the OCS emulator.

Is there a connector anywhere in this circuit, or is it just one wire?

Thanks.

EvilDMP

there should be a 24Pin (M60A, Forward Connector) and 32Pin (M60B, Rear Connector)... the OCS runs into the 32 Pin Connector (M60B) at Pin19, you will be looking for a mostly white wire with a grey trace.

heres the plug layout for M60B, note the little wings for orientation ive highlighted Pin19 for you...

richydraper said:

EvilDMP

there should be a 24Pin (M60A, Forward Connector) and 32Pin (M60B, Rear Connector)... the OCS runs into the 32 Pin Connector (M60B) at Pin19, you will be looking for a mostly white wire with a grey trace.

Click to expand...

You were quite right, while lying contorted under the steering wheel I misread 32 as 22.

Anyway, there was a perfectly good connection from the signal connector on the OCS emulator to pin 19.

So, I think that either I have a faulty airbag ECU, or the OCS emulator is faulty, and my guess is the latter.

I'll order a new one and see how I get on! Thanks for all your help.

i highly doubt it will be ECU, throw an emulator at it and let us know how you get on

Thanks very much to all for the advice and suggestions.

I received a new mat emulator in the post today - and it did the trick. So clearly the old one was faulty (wish I'd tried that before tearing half the car apart).

On with the show!