TD Bank on Thursday promised an “enhanced testing program” for its popular Penny Arcade coin counters before returning them to duty at its 1,300 locations.

The bank unplugged the machines on Wednesday after a report revealed that each of a handful that were tested had shortchanged customers.

The machines, which feature an animated “Penny” on their video screens, are popular with youngsters cashing in their piggy bank coins.

The bank refused to answer questions about how the machines ended up apparently cheating customers anywhere from a penny or two up to 15 percent of their money, according to the report from NBC’s “Today.”

Instead, in a statement, it would only say: “We place a premium on the integrity of these machines, and that’s why we clean and test them twice daily to confirm accuracy.”

The “Today” report also found that Coinstar counting machines, mostly in supermarkets, counted the exact amounts of coins poured into them.