I believe I paired mine with Duo SC which is for a combined Speed/Cadence sensor. The PC7 likely just takes the speed info from the GSC-10 and gets cadence from the SRM.

ok I will try but it reallly supposed to be with '' plus''

btw, do you have a number on your ''paired'' window in pro +, kind of serial number for your sensor??

I tried, I obtain the same thing, from Duo Sc or DUO s, found and the number is ''1''

Have you paired the GSC10 with a garmin or other device? i.e. have you confirmed the GSC10 is working properly? You might need to reset the GSC10 or put a fresh battery in and reset using the little button.

Mine pairs on the Duo SC setting and displays the serial number 22286.

oh, finaly I think we cant paired pc7 with GSC-10 from garmin, look what I have from srm manual:

Power= SRM PowerMeter
Heartrate = Suunto Dual HR Strap , Heartrate Plus= Garmin HR Strap
speed, cadence = Suunto QR Front Wheel Skewer, Speed Plus= SRM VDO Speed Pod (fork or chainstay) , Speed DUO S= Duo-Trap Speed ONLY Speed/Cadence DUO SC= Duo-Trap

so nothing on GSC-10

yes, it works fine, last week everything was ok with my garmin 510....

I've been using the gsc10 with a pc7 for speed. The pc7 has nowhere else to get speed so it must work.