Technical Ducatto 2019 cambus communication fault

[acairns]

I have a Burstner motorhome based on a 2019 Ducato 2287cc 150hp engine. The airbag warning light on the instrument cluster is on and won't clear, the yellow light on the centre consul is also showing the passenger airbag is disabled. I have tried to reset the airbag by using the settings menu however the airbag system is not showing in the menu. I had a local garage run a obd scan which is showing a code referring to a cambus (think that is correct) communication fault with the instrument cluster. Before I head down to Fiat Commercial and be told my vehicle is out of warranty and it is going to cost a shed load of money, Is this issues something any of you guys have seen before and more importantly is there a way to reset the cambus? Oh yes and since the garage did the obd scan the odometer is now flashing continuously. Can anybody help me please?

 

[Communicator]

Hi @acairns,

I cannot help much as my experience is with an older 2006 x244 model. However please note that in common with most other recent vehicles, post 2006 Ducatos are controlled by a network of computers. The data highway which connects these computers is called the "Canbus" with an"n". For more general information on this you could google "canbus" or search on Wikipedia. Ducato specific information is contained in the "x250 Training Manual" which can be downloaded vie the forum downloads section. See tab at top of page.

If a computer on the canbus is replaced a procedure called "proxi alignment" is required so that all of the computers are aware of each other. If a computer has suffered a transient fault it may be necessary to carry out a new proxi alignment. Other causes could include physical damage to the canbus wires.

I note that your original fault was with the airbag system which is connected via the canbus. I am aware from browsing this and several MH forums that some Ducatos from about 2018 suffered from a bad batch of airbag controllers, and that Fiat accepted some responsibility. Perhaps you could try searching for Fiat or Ducato airbag fault? I believe that the flashing odometer is a warning that all is not well on the canbus. I think that this will be mentioned in the vehicle handbook.

I hope that some of the above points in the right direction, but there others on forum more experienced in later models who should be able to provide further guidance.

 

[acairns]

Thank you for your feedback, I will research airbag faults on other forums. Again thanks for your response. All the best Alastair.

 

[theoneandonly]

The dodgy air bag ecu has been around since 2012. The canbus error is due to the system being unable to talk to the airbag ecu. Some errors can be read/sorted with multiecuscan but not many. An internal flag may be set which prevents comms, companies like crashdata can reset this flag but not fix any other issues. The first thing to do is check all connections under the 2front seats and have a read. The reset rarely results in a longterm repair. New ecus are of a more relable design. The most likely route will be a new ecu from coastal motorhomes and a self proxi alignment (or friendly garage) or a visit to fiat proffesional.

 

[HughJampton]

Failure of the Ducat0 airbag ECU has been a common problem, and is at epidemic levels at the moment. There are various faults reported, but in general they will cause the airbag fault light to illuminate, and often associated warning lights such as the passenger airbag and seatbelt light.

You really need someone to read the codes with Fiat-aware equipment. DIY via MultiECUscan is an option - but at a cost (c£100 if you have a compatible laptop).

Depending on the resulting code, there are two basic options:

i) replace the Airbag ECU with a new one. (That will require the new unit to be coded to the vehicle - "proxi-aligned"). ISTR that, under certain circumstances Crashdata can supply a new unit that doesn't need recoding. MultiECUscan will proxi-align a vehicle.

ii) have the existing ECU re-flashed by someone such as Northern Autotech or Crashdata. Once returned, the "repaired" unit doesn't need coding to the vehicle (since it is the original). If this works, it is considerably cheaper, but experience of longevity seems to vary (I'm 8-months into a reflashed unit with on a 2018 'van with no issues so far).

DIY removal/replacement of the airbag unit is not particularly difficult, but given the pyrotechnics involved it does require care and a specific sequence. The code-reading and proxi-alignment is the awkward bit (without having MultiECUscan available).

The flashing odometer is a symptom of the Canbus system not being able to communicate with a node that it thinks should be there. If that occurred after the diagnosis work, then it is likely (but by no means certain) that investigation work has caused the airbag ECU to go "offline". Again, diagnosis really needs a code-reader that is Fiat aware.

Though the odometer problem might be associated with other issues, it's quite likely that proper remediation of the airbag problem will remove that additional symptom.

 

[acairns]

Failure of the Ducat0 airbag ECU has been a common problem, and is at epidemic levels at the moment. There are various faults reported, but in general they will cause the airbag fault light to illuminate, and often associated warning lights such as the passenger airbag and seatbelt light.

You really need someone to read the codes with Fiat-aware equipment. DIY via MultiECUscan is an option - but at a cost (c£100 if you have a compatible laptop).

Depending on the resulting code, there are two basic options:

i) replace the Airbag ECU with a new one. (That will require the new unit to be coded to the vehicle - "proxi-aligned"). ISTR that, under certain circumstances Crashdata can supply a new unit that doesn't need recoding. MultiECUscan will proxi-align a vehicle.

ii) have the existing ECU re-flashed by someone such as Northern Autotech or Crashdata. Once returned, the "repaired" unit doesn't need coding to the vehicle (since it is the original). If this works, it is considerably cheaper, but experience of longevity seems to vary (I'm 8-months into a reflashed unit with on a 2018 'van with no issues so far).

DIY removal/replacement of the airbag unit is not particularly difficult, but given the pyrotechnics involved it does require care and a specific sequence. The code-reading and proxi-alignment is the awkward bit (without having MultiECUscan available).

The flashing odometer is a symptom of the Canbus system not being able to communicate with a node that it thinks should be there. If that occurred after the diagnosis work, then it is likely (but by no means certain) that investigation work has caused the airbag ECU to go "offline". Again, diagnosis really needs a code-reader that is Fiat aware.

Though the odometer problem might be associated with other issues, it's quite likely that proper remediation of the airbag problem will remove that additional symptom.

Thanks for your feedback, I think a trip to Fiat is the best first step. Again thanks.

 

[CheeseMonster]

Thanks for your feedback, I think a trip to Fiat is the best first step. Again thanks.

Just buy a new airbag ecu and a copy of MES.

 

[HughJampton]

It could be a steep learning curve if you're not accustomed to such work.

(and the copy of MES, for diagnosis reasons, should come before any purchase of a new airbag )

 

[Communicator]

Just buy a new airbag ecu and a copy of MES.

@acairns may not have a Windows laptop to run MES. An alternative middle course would be to buy a cloned airbag controller from Crash Data, which would be plug and play. For more info, may I suggest reading this Motorhome Fun thread.

 

[theoneandonly]

If a windows laptop is not available is alfaobd and an android device not an option. USed it for other aspects but not sure it can do a proxi alignment