Currently Being ModeratedFeb 20, 2013 8:34 AM (in response to shirl-red)
Verify that the Canon printer has the latest firmware version installed. See the printer documentation or contact the printer vendor for support. Is the printer connected to your network?
Read through this: http://support.apple.com/kb/ht4356
Currently Being ModeratedFeb 20, 2013 11:05 AM (in response to shirl-red)
Your profile says your iPad is still running iOS4, which is pretty old. Is that accurate? I don't think iOS4 supports AirPrint.
To enlarge on JimHdk's comment, Canon says the MG3150 must be at firmware level 2.000 or higher. You can view the firmware level on the Nozzle Check Pattern output.