The OBC has two functions: AC/DC section to charge the HV battery using an AC supply, DC/DC part that tops up your 12V aux when READY.
Therefore yes, if CHAdeMON works, the OBC is the primary suspect..
Managed to get the car to the local chademo as thought I had just enough to get there and back if needed. Arrived and plugged in and initially the car then refused to charge or connect. Briefly started and then got a yellow car with exclamation mark on dash.
Sat for five minutes and tried again - this time it did charge and was not certain it was charging so stopped it and was sent a bill for 61p for 0.81Kw so then knew it was working.
Started the charger again and it then worked for 21 mins before dropping out on its own accord using 1.571Kw costing me 1.18GBP
The charge had gone from three bars on the dial to about 6/7 so assume that the chademo thought that this was 80% of the battery and so it stopped. Did not think to restart again as I was only glad that I had more charge than when I started and could get home!
This I think from what has been discussed proves I currently have a problem with the OBC which similarly dropped out again when I got home although it did plug in and I had three whines on the I assume aircon before it gave me the flashing yellow car with ! mark.
Next question is can I try to repair the OBC similar to the way I have seen on this forum or do all of them have different issues and can I measure anything to see what is the issue?
Secondly is there anyway I can test the OBC or swap the OBC from the white car - which has no black box with indicator lights with the "working" black car with the brick type charge lead?
finally even though the chademo clearly was working am I correct in my assumption that the battery pack is not the best when it drops out at 80% charged and is still two bars below the mid point of the scale.
Was very pleased I had tried this and managed to get to the chademo - thank you for the advice