[Roy V70 850]

Just fitted a tow bar to my 2004 v70 D5. It came off a v70 with a 13 pin socket fitted. I plugged this into the grey connector and tested it using a 13 pin to 9 pin adapter to my light board for the bikes. All the lights worked ok except for the indicators.

I read somewhere that this should show up on the dashboard but I get nothing.

Has anyone any ideas. Have I missed something obvious?.
Thanks