Grail:on problems

[P A Price]

I have recently fitted a Speedbox 3 to my Grail:On. It “lags” intermittently during the ride and occasionally cuts out for a few seconds, the Speedo shows 0mph and then comes back in... The speed setting does not save and when switched on I get an error code 503. This disappears after riding a short distance. My lbs have changed both the speedbox and screen but the problem persists - any ideas?

 

[urastus]

I have recently fitted a Speedbox 3 to my Grail:On. It “lags” intermittently during the ride and occasionally cuts out for a few seconds, the Speedo shows 0mph and then comes back in... The speed setting does not save and when switched on I get an error code 503. This disappears after riding a short distance. My lbs have changed both the speedbox and screen but the problem persists - any ideas?

Have you tried removing the speedbox to see if the problem persists? I'm guessing it won't.