Citroen C5 2006 fault code U0028

[Resecen]

Hi I was driving down the motorway in France. I stopped for a coffee, restarted, drove a few minutes then realised that although the engine was running fine, the dashboard was basically off - all gauges, speedometer etc on zero. That's a bit worrying when you're driving at 89mph. I stopped, restarted, same problem. Pulled into a service station, had another coffee, restarted the car and all fine again. In fact has been ok for last 3 hours of driving. I checked with OBD2 meter and fault code was U0028 which seems to a lot of stuff. Any ideas? Id take it to a garage but my experience is they really don't understand the electronics (or are there specialists I could go to?) Thank you

[GiveMeABreak]

That's a generic fault code relating to electrical / data networks and is usually present within a defined system, which I doubt your generic code reader can provide. It really needs Lexia for the context in which the fault code appears.

[Resecen]

Thank you for that. What is the best sort of person to contact to do that - a Citroen garage or what? (Last time I had an electrical problem they weren't much good)

[GiveMeABreak]

If not using the dealership, you need a garage with a Lexia / Diagbox diagnostic kit and software to get the other fault code associated with this one or at least it will tell you under which component or system the fault is presenting.

You haven't provided a VIN so we don't know what engine you have or whether you have a Full CAN or CAN VAN electrical system, but assuming its CAN and a 2.0 or 1.6 Hdi then this is what I have and it concerns the instrument panel communication:

Fault Code:	U0028
Description of Fault:	VAN communications: Fault on the Comfort VAN networks or the instrument panel. Fault on the Comfort VAN networks or the instrument panel (For at least 9 seconds) (9 datastreams).
Conditions for Fault to clear:	Ignition On
Downgrade Modes whilst Fault is active:	None, apart from Warning lamp (MIL).
Symptoms:	Not applicable
Suspect Areas:	CAN network

So this will be similar for a 1.6 HDi, meaning there is a problem with the electrical communication with the instrument panel.