Error code

Riding home from work today the orange FI light came on. When I put the bike in neutral I got 1 long flash and 7 short flashes.
I read that the long flash represents 10 and each short flash is 1. Is this correct?
If so then looking at the manual I have 'Blink code' 17 - Lambda probe for rear cyclinder - malfunction.
The sensors are still plugged into the exhaust but the wires are disconnected
Its an '07 with Akropovic Evo's. It has a Powercommander fitted, no TuneECU.
I've done a bit of a search and it seems that if the sensors/wiring aren't dirty or visibly damaged, the answer may be to turn them off in TuneECU, however I don't have it.
Any suggestions?

The rear O2 sensor blanking plug resistor, if you have them fitted, has failed - either replace it (I have unrequired spares) or buy/borrow a TuneECU cable and switch the O2 sensors off.

Thanks mate - I've pm'd you.
Presumably there's no actual harm in continuing to run it like this in the meantime?

PM back - just got the same error tonight - ECU defaults to 'get you home' mode and engine runs crap.......

Are you sure the O2's are just disconnected? You would have had the error code(s) for one or both if so. TuneECU is what you need.

Mine seems to run fine, just gives the error code.
I haven't had the chance to check it over, I suppose a sensor could have just come loose?
Is there anyone in the Greater Manchester/Northwest area that has a tune ECU cable I could borrow?