Tuner in Cubase 7

Doe’s anyone know how to work the tuner in Cubase 7 ? I look at it in the guitar channel, push the buttons, nothing happens! I can generate a tone in one of the onboard synth’s but I just thought the tuner would be easier, thanks.

Have you got it in an insert? Is it enabled and not bypassed?
More detail would go a long way for anyone trying to help you.

Make the tuner an insert in the Cubase input channel for your guitar (not the output track channel) and it should work.

and disable direct monitoring.