Outside temperature sensor

[wilsofar]

I know its not essential but every temperature sensor I get (admittedly cheap eBay purchase) is inaccurate .(from 5 to 10c low).

Is there any way to alter the signal sent to the display (perhaps something in line)?

I know I'm being fussy but I would like it to be as accurate as possible .
I don't have any evidence that genuine Renault parts would be any better!