I would re-word a bit. Don't check between pins one and nine, repeat the measurement proceedure for pins one and nine ( the anodes ).

If you attach negative lead to the cathode( pin 3 for pin 1 anode , and pin 6 fo the pin 9 anode ) or to of the LED string, you can measure current w/o extinguishing the LED's. Not exactly remomended, as there is less room than the ground terminal offers.

Thanks again Colin for teaching me that cool trick.
regards,
Dogulas