BMW dealer - does this sound right?

[Tindersticks]

My Uncle (who is not mechanically minded at all, and not local so I can't deal with this for him) has an F30 that's showing a CEL. His neighbour hooked up Bimmercode and it's showing an error 180001 'Catalytic Converter: efficiency value too low'. He took it to a local garage who said this was usually either an O2 sensor or cat, and the car is driving absolutely fine that it may need a software update. The car had been sat for a while over the winter so they cleared the code to see if it came back. After a couple of drives it hadn't but it is now showing within Bimmercode as the same code but with 'would not show a fault' so there is no CEL. He took it into his local BMW dealer for more diagnostics and after they'd spent 2 hours on it they came back with:

Software is up to date, but as there is no CEL we can't run anything on it and can't tell you a thing.

Are they stiffing him for extra hours work or does that sound legit. It's a long time since I used a main dealer rather than an Indy specialist.

[mmm-five]

Lots of codes will be stored for temporary/one-off issues. It's only if the issue reoccurs or becomes serious will a CEL will be shown.

[BlackStang5point0]

Maybe I've misread your post but I'm not really sure what you're asking.... The car drives fine, it's been into BMW and they have confirmed the software is upto date and no CEL showing.... What's the issue..??

[Tindersticks]

The CEL has come back a couple of times after being cleared. My question was more whether BMW should be able to diagnose better based on the fact that the code is always 180001.

I called a local specialist earlier and he succinctly said ‘that’s bks’. The presence of a CEL doesn’t determine the presence of a fault.

[trevalvole]

Does he tend to only do short journeys in it? I'm wondering whether things like the O2 sensor have got coked-up and it may just need a decent drive to burn it all off. That might account for the intermittent nature of the fault too.

[Tindersticks]

trevalvole said:

Does he tend to only do short journeys in it? I'm wondering whether things like the O2 sensor have got coked-up and it may just need a decent drive to burn it all off. That might account for the intermittent nature of the fault too.

I wondered that. I think he’s only done about 2000 miles in it in the last year and most would have been short. I’ll suggest an Italian tune-up!