Getting this constant error message , any ideas?

Failing sensor batteries will show this fault.
If the sensors are original, the batteries could be past their best by now.
The same can apply to those fitted in new old stock sensors also.

Warwick 2011 L322 TDV8 A/b Orkney Grey
2008 Defender 90 XS TDCi Java Black
2002 L322 TD6 Vogue Zambezi Silver (gone but not forgotten)
And one or two bikes - Ok, maybe more than one or two....