Taxicab meter didn't meet TLC taximeter specifications
In the last published text of old Chapter 3 (taxicab specifications), Rule 3-04(a) lists what a taxi meter unit must be: fully electronic, sealed by a licensed meter shop, tamper-resistant, able to print passenger receipts and TLC audit totals, with non-erasable memory and backup power. This charge is dated 1984, when an earlier version of the specifications applied, so its exact wording then is not available.
Former TLC Rule 3-04(a)TLC Rules, old Chapter 3 – Taxicab Specifications (last version)