There is no command to check if VP5300 and L100 are paired. But there is a command to check the front removal status of the VP5300. You can send the 04-22 command with data 03. If the VP5300 front removal is activated, it will respond with success. In order to activate the VP5300 front removal, the L100 must be paired with it first. This is a roundabout way of checking if the two are paired.