I managed to fix my TZ today, it appears the problem was SW 51, when measuring this switch it won't show 0 or infinity ohms but very high resistance (this was also shown as an error - SW 51 Gum Popper Lane ), I operate the switch a few times & then I was able to measure 0 & infinity ohms. I then played a few games in which the powerball was detected & working as it should. I look at the switch matrix & found that SW 51 shares the same column as the slot proximity. I assume the switch must of being dirty or stuck in between on/off & will probably need replacing in the near future.
Thanks to everyone who provided help.