The "missing" fault code????

[mopardave]

So, after having my coil light illumination diagnosed as a fault with a flap in the manifold 5 weeks ago........

Right, stay with me here gents! Today, I took the van back for them to deal with the claim and do the MOT. Imagine my surprise when I get a call to ask if I've erased any fault codes!!! No I haven't so what's the problem? My van now isn't showing any fault codes after two coil light illuminations and a drop in power. On both occasions, I switched the ignition off and back on again and the problem went away. They diagnosed the problem 5 weeks ago but didn't have the part so I said I'd bring it back when the MOT was due and they could do it all at the same time. Long and short of it is, they now wont process the claim because the fault code has disappeared and VW wont allow it. My extended warranty expires on the 1st Sept so that's convenient!! They said they'll honour a warranty claim on a good will basis if it happens again.........but they've yet to specify a time limit. I did suggest that their Master Tech may have erased the fault code when they diagnosed it back in June but the workshop manager says he wouldn't do such a thing.
Anyone got any thoughts on this because it would appear I haven't a leg to stand on.
Cheers gents.

 

[mmi]

They diagnosed the problem 5 weeks ago

the fault code has disappeared

The challenge is that fault codes have different "levels"
1) Active and dash light on
2) Pending/recent (no dash light) - if the fault won't get "refreshed" it will eventually fall into category 3. This will happen somewhere at approx. 500-1000 km without a new "incidence".
3) A thing in the past

The problem is that VAG ODIS recognizes only categories 1 and 2.

However, fortunately the faults are still stored in the ECU as long as they are not explicitly erased. E.g. VCDS (and OBDeleven) shows also faults in category 3.

I think you need to emphasize that they diagnosed the fault 5 weeks ago. You might consider mentioning that ECU stores distance driven since the faults were erased - in ECU memory location IDE00584.

Combining those pieces they should be able to convince themselves... when the fault codes were actually erased last time.

AFAIK when "ODIS Guided Fault Finding" is executed, the existing fault codes must be erased to finish the process correctly... certainly could be different on RHD vehicles

PS. What was the problem?