TECH HELP EDITOR
Base vehicle expert
QWill my airbag ECU fail again?
I wrote some time ago regarding the airbag warning light on my 2018 Fiat Ducato. As there is no Fiat franchise garage near me, I had a scan done at a reputable garage, which deals with lorries and motorhomes.
The scan showed the codes B0102-00 (connection to ECU grounding) and B0127-13 (driver's seatbelt switch). I was going on holiday, so I booked it into the garage on my return.
It removed the ECU and sent it for repair. However, the report then came back that it was unrepairable, so I authorised a new one to be coded and refitted at a cost of £700. When I collected the vehicle, I asked what warranty it came with it and was told if the vehicle battery dropped low, it would blow the ECU and any warranty would not count.
I always keep the ‘Van plugged in at home and the display shows both batteries to be charged. I also have a 100W solar panel fitted.
The ‘Van never fails to start on first turn, so do I need a new battery or is the garage just trying to wriggle out of the warranty? What legal protection do I have if it fails again (I can't face another £700 bill)?
And, finally, how can I tell if the solar panel and/or the electricity supply is charging both batteries? If the ECU is so temperamental that a mere drop in voltage can blow it, why has it never been a recall?
The garage suggested buying a smart charger and plugging it into a socket then connecting it to the vehicle battery with crocodile clips but, with the battery being in the floor, this seems such a faff.
David Wright
A Your problems and service from your chosen garage do seem to be extreme, and I feel you may not be getting the best service, advice or price. For example, a new Fiat ECU unit is less than £300 and would come with an unconditional 12-month warranty. Coastal Motorhomes (on Ebay) sells them for £250.
There is no history that low starter battery voltage damages the ECU. Also, your hook-up and solar set-up should be sufficient, providing they trickle-charge the starter battery once the leisure battery is charged.
Without knowing what conversion you have it is difficult to check if this feature is present, but on a 2018 vehicle I would expect it to be present. Even so, it is not difficult to add a Battery Mate or Battery Master to provide this feature.
A digital multimeter connected across the starter battery to measure voltage after a night connected to the mains hook-up is all you need to check this. If this voltage is above 13V, then it is getting some charge. You don't need another smart charger.
The fault code suggesting that the ground wiring should be checked out is worth following up by a Ducato expert.
Clive Mott
In the majority of cases that I have heard of over the last few years, the ECU has not been repairable and I
