If not, you're not alone.
There are four combinations and they all mean different things.
- The cab is off-duty when the "off-duty" sign is on and the medallion number is off.
- The cab is available when the "off-duty" sign is on and the medallion number is on.
- When both the "off-duty" and the medallion number are on, the taxi is available for trips in the direction the cab driver is heading.
- When both signs are off, the cab has a fare and is not available.
"If I don't see the middle light on and the two one's on the side are lit, I don't go for it. I have to see the middle light on, the two sides off," said one passenger.
The Taxi and Limo Commission chairman says it's time to put the brakes on the decades old system.
His solution is to ditch the "off-duty" lights and keep the medallion lights.
"If the light's on it means you're available to be hailed down. If the light's off, it means the taxi is unavailable, either because someone is in it or the cabbie is off. That's it - simple. On-available, off-not available," said David Yassky, TLC Chairman.
"That's perfect," said a passenger.
Medallion owners will pay the cost of simplifying the signs which, according to the Taxi and Limo Commission, can happen with the placement of an insert to cover up the words "off-duty".
Passengers can expect to see the new signs beginning in the fall.
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