OK, so I've tried a few different things today. In summary, I think this is an issue of compatibility with
MES. My ELM connection seems to be functioning fine, although I do get a "Latency too high" error when performing the "Scan for interfaces" option in the settings. But anyway...
In
MES, I tried the 'Bosch Motronic Me7.6.3' under the Fiat Panda '06 1.4 16V menu. I was hoping this would work as it's my ECU model number, but I got a "ELM327->OBD Connection Failed" error". Perhaps the Panda ECU is slightly different despite being the same model?
However, in AlfaOBD there is an option for 'Bosch Motronic MeD7.6.3' under Grande Punto and I
was able to connect to this successfully! But, similar to my experience when using
MES to connect to 'Me7.9.10', the odometer reading is incorrect (couple of thousand miles off), so maybe the other readings aren't quite right either.
In any case, there doesn't seem to be any fault codes stored so I've achieved what I need to. I've already purchased
MES, but seems like AlfaOBD would be useful to have also if you have the StarJet (and presumably the T-Jet too). At least until a time when
MES properly supports the ME7.6.3.
Yes, I can quite reliably replicate the problem by turning the ignition fully on very quickly. If there is a momentary pause between initially turning the ignition on and then starting, then there's no battery light and power steering works fine.
Strangely, I don't get any error codes (tried with my ELM interface and
MES/AlfaOBD, and a generic OBD reader with Torque Lite). None are stored, and none are present even when the battery light is on.
It's strange that when I have this problem, the battery light is on, and the power steering is not functioning, but yet there is no PAS error light. It's impossible to turn the steering wheel, it's as heavy as when the car is turned completely off. It's as though the ECU thinks the PAS is working correctly, but it's actually shut down. There's 14.1v at the battery, and the CAN Info reports the same voltage too, so it's not a lack of voltage on the CAN bus...
I wonder what is missing from these remanufactured alternators that is present in an original Fiat part
As my problem is not only the battery light, but also the PAS turning off, I might check connections to the PAS motor...