Car dies sudenly whilst driving (very dangerous)

I have a Citroen C3 Picasso VTR PLUS HDI 1560cc. Diesel. 2009. 67000miles.

Car dies suddenly whilst driving and the dash says air pollutant fault. As this happened the engine auto diagnostic symbol was lit and not flashing. According to the manual, if lit it indicates a fault in the engine management system. If flashing, which it was not, that would indicate a fault in the emission control system.

Fault codes read by a local garage with a snap-on tools diagnostic kit, not a Citroen dealer, were;
Yellow warning triangle – Antilock Brakes - Codes: 2
U1308 Engine ECU operation
U1108 No communication with engine ECU Data invalid

As known common faults, the crankshaft positioning sensor was replaced with genuine Citroen part. EGR valve was cleaned but not dirty anyway. Fuse box checked for damp or rust (none). Earths checked too. Oil and water levels checked. It was noted front anti-roll bar links need replacing but not an MOT failure, just slight wear.

As an aside, please note front and rear pads had been replaced by previous owner by himself and not at a garage. Don’t know if he unwittingly disturbed any sensors in process. He also did his own oil and filter change but he was an ex-mechanic so rightly assumed he knew what he was doing.

Apart from that vehicle has a good service maintenance record. Everything looked clean inside the engine when I bought it as inspected by a mechanic (but not electrical computer expert) when I bought it.

Also note the first time the engine just died whilst driving the warning on the dash was oil pressure low. I was not driving it when this came up so cannot verify. But I have driven it since when the above problem has been repeatedly come up.

Any advice appreciated as my local garage at a loss as what to do next without throwing more money at the car and no guarantees a fix can be found. Thank you for reading.

U1308 Engine ECU operation
U1108 No communication with engine ECU Data invalid

Looks like an ECU fault,or wiring loom to the ECU fault.

It could be the bad earth for the ECU, check the earth point and the battery area for corrosion of the earthing.

It will take a fair amount of experienced (with ECU and wiring) to diagnose and eventually fix though.