Not sure on Aristocrats, you can try unplugging one of the meters (with power off to the machine) just to see if it causes an error when you power back up. On some older machines the meter presence is not sensed, the mpu will not know if they are disconnected, my IGT PE+ is like this. But other machines do fault if the meters are unplugged, it was required by regulators or casinos for financial bookkeeping integrity. On some machines you can add a jumper wire to the meter connector or backplane and it will let the machine run without the meters, I think some of the WMS and Bally machines allow this.