The traces demonstrated that the car closed the connection imediately after apparently calling for SMS message 16 from the SIM card.
My only regret is that I did not try and diagnose, which message precisely by deleting selectively to pin it down.
Message 14 was corrupt in that it contained only symbols and foreign language characters and looked like interpreted binary data. Logically you would think it was this message and perhaps the system multitasks or multithreads so that it was handling this message while at the same time calling for message 16. Message 16 itself was a message triggered by Vodafone thanking me for staying with them. I guess it was triggered by me moving my old SIM into the new chassis that Vodafone had sent me. The message contained a web address. The only unusual character was the trailing slash “/”. The display system in the Bentley does understand URLs because the help pages, for example are just web pages fetched from the navigation DVD. So perhaps it tried to fetch the web page and it failed but I think I am “clutching at straws” as we say. However, as this would have been the first message on the new phone chassis and thereafter it did not work, there is strong circumstantial evidence that this is the culprit.
As you see it was a pity that I did not take a more diagnostic approach to find out.
Many many thanks for taking the time to look at the traces and fix the problem.