Hi headwest,
If you are using a Phantompatch on your TM 5402 HD then that could be causing some kind of issue with an original subscription card... even with the patch switched off... have you tried using the card with just the Technomate Original Software on the receiver...?
Using the card in a Diablo Cam (without a KEY.BIN file) might also be worth a try...
PS
Are you sure that you've got the card inserted the right way up... 'Invalid Card' messages also occur when the built-in cam cannot see the chip on the card...
I hope this helps...
Best Wishes,
Zorch