Technical airbag light on (MK1)

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Technical airbag light on (MK1)

electricFuzz

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Hi,

I was doing some repair on my father's punto MK1. Like an idiot I removed a fuse without disconnecting the battery first. We now have the airbag light on the time. I think nothing's wrong, it just fired an error and copied into memory.

the fuse I removed is under the small black block under the windscreen in the bay engine.

Where is located the ECU module ? (behing the radio I read but not sure). I'd like to write down the module ID.

It seems that those cars don't have a OBD2 port but rather a diagnostic port for the airbag module. Is there a recommended tool to talk to it and try to reset it ?

If I change the module, is it a plug-and-play type of operation ? (I guess it is considering how old the car is)

thanks !
 
The airbag module/ecu is located behind the center console, between the gearstick and bulkhead. Its mounted to the tunnel section.

What work did you do when you disconnected the fuse? Have you tried disconnecting the battery for a couple of hours and reconnecting?

From memory I dont think either MES or iaw ecu scan will do airbag but cant confirm without checking.
 
Hi Noddy, thanks for the reply.


What work did you do when you disconnected the fuse? Have you tried disconnecting the battery for a couple of hours and reconnecting?

nothing to do with the electronic and the sensor of the car. We changed the oil pan, the timing belt, the thermostat. I disconnected the battery for less than a hour. Maybe I'll try to remove the connection for several hours.


From memory I dont think either MES or iaw ecu scan will do airbag but cant confirm without checking.

That's what i'm afraid of and at the dealership it can cost an arm and a leg. Let alone if they still have the tool to read the module memory. (I had the experience for another car which is even more exotic than a fiat punto! )
 
MultiECUScan can connect to the airbag and ABS modules, you can't connect to it from the normal diagnostics port by the ecu as thats just for the engine ecu..

Theres another port (same fiat 3-pin) for the airbag, thats the one inside under the centre console area. And theres another one for the ABS system which from memory is by the ABS pump in the engine bay - sorry its been about a decade since i had a mk1 punto so thats as precise as i can remember.

But look near the ABS pump for another 3-pin diagnostic connector the same as the one by the ecu. Connect in the same way as ECU, so fiat 3-pin adapter to KKL/Vagcom cable to laptop and it should connect up and read/clear codes just fine.
 
Hi sorry I haven't given news about the car. I didn't have much time to work on it

But look near the ABS pump for another 3-pin diagnostic connector the same as the one by the ecu. Connect in the same way as ECU, so fiat 3-pin adapter to KKL/Vagcom cable to laptop and it should connect up and read/clear codes just fine.
No ABS on the punto but I think I found the 3-pin connector hanging behing the front console, behind the radio.


I have to get back on it anyway, the car won't pass safety regulation otherwise. The car drives fine and we've make too much work(the car is possessed...) to toss it.


next step : find out the serial number and identification code of the airbag module and find a new one (little hope that dealerships can be of any help for such old car). I'll let you know ! thanks !
 
You don't have to change the airbag module if it worked correctly before disconnecting the battery. You can just erase the error and it will work as normal again.
You already found the diagnostic connector, now you need a 3pin to OBD adapter and VAG/KKL OBD plug (both cheap on ebay/aliexpress), free version of MultiEcuScan software will access airbag module normally (the only thing you can't access with it is ECU, you need a paid version for that, but luckily there is a similar free program IAWscan2 to access ECU)

If you still want to replace the module for some reason, get one with the same part number as there are multiple versions available and i don't know if a different version will work correctly. Best to just use the one you already have.
While you're at it, check if there are any signs of heater core leaking, it is directly above airbag module and will destroy it if it leaks. There was a recall regarding that and fiat started putting little plastic shrouds over the airbag modules so in case of a leak, coolant is diverted away from it. Maybe those plastic things are still available from fiat or you could fabricate your own if you can be bothered.
 
You don't have to change the airbag module if it worked correctly before disconnecting the battery

It did work correctly. I didn't know about the multiEcuScan program. I think I'm going to order the cable and stuff. It could be less harmful than tinkering with the old airbag module. I need to find a windows machine though.
thanks Frank !
 
what happened? Did you manage to connect to the airbag ecu?
Nope I can't connect to the airbag. But I suspect that I don't have to correct driver. I installed the ones from the manufacter of the CH340 with no result. However the blue VAG/KLL leads to the driver on this page :


I also asked the aliexpress seller for the software as they don't ship the CD anymore. I'll investigate more next week, I'm using someone else laptop.
thanks !
 
open device manager (run > devmgmt.msc) and see if you have any unrecognized hardware that might be your KKL device. If it's there, you can try to manually find a driver.
To do so, right click on unknown device > properties > details, then find Hardware IDs. Copy that in google and see if there are any drivers available for download. Beware of various bogus websites or driver "packages" or "installers" that are several MB or larger in size. It is usually less than 1MB total and contains an .inf and .sys file. Then go back to device manager, select unknown device and install driver manually by selecting the directory that contains your downloaded driver.

If there is no unknown device (you see your kkl adapter on the list and no question mark next to it) then the driver is already installed and something else is the problem. In MES you need to select the right COM port for your kkl cable, myb that is the problem.
Did you connect the power leads (wires with alligator clips) on your 3 pin cable?
 
I've never really had issues connecting to anything so I'm not much help there.. windows has always recognised the cables and installed drivers without me needing to do anything.. I have had to set COM ports before though in MES, and i tend to find once its working if you remember what USB slot you connect to then you never have to mess with settings again, if you use a different one you sometimes have to change the COM port again or mess with the settings.

This might sound really obvious but remember you still need to connect the 3-pin crocodile clip to 12v+. If your using a a wire inside the car make sure its a permanent live and not a switched live. Sorry to state the obvious but people do forget sometimes :)

If you really struggle and can't work out why you might just have a dodgy KKL cable, always seems to be plenty of them about
 
Hi sorry for the delay.
This might sound really obvious but remember you still need to connect the 3-pin crocodile clip to 12v+. If your using a a wire inside the car make sure its a permanent live and not a switched live. Sorry to state the obvious but people do forget sometimes :)
Did you connect the power leads (wires with alligator clips) on your 3 pin cable?
obvious enough that I though the power was taken from the ODB connector. doh ! it might be where the issue lies...But if the key is on the ON position , isn't the airbag module powered ? Does it need an external power for debug purposes even with the key ?
open device manager (run > devmgmt.msc) and see if you have any unrecognized hardware that might be your KKL device. If it's there, you can try to manually find a driver.
To do so, right click on unknown device > properties > details, then find Hardware IDs. Copy that in google and see if there are any drivers available for download. Beware of various bogus websites or driver "packages" or "installers" that are several MB or larger in size. It is usually less than 1MB total and contains an .inf and .sys file. Then go back to device manager, select unknown device and install driver manually by selecting the directory that contains your downloaded driver.

I had no issue with WIndows finding the hardware id and driver (from the manufactor of the chip). It looked like the airbag didn't want to talk.
 
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yes you will need to run a permanent 12v source and ground to the crocodile clips on the fiat 3-pin adapter for it to work.
I'm going to test it with power this time !
 
I Fixed the problem ! the light went off !

Now I need to deal with the non-working speedometer.

thanks you very much for the help !
 
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