What does it mean when t he light is on that says "maintenance required"? on 2003 Honda Odyssey

I had my van services including oil and filter change in April, 2012 and does not require maintenance again until June, 2012

Asked by for the 2003 Honda Odyssey
We have had that trouble as well, intermittently for a few years now. The maintenance req'd light comes on even though we are current with our oil changes and services. The first time it happened we took it to the dealership, who told us that the light has to do with the gas cap (which we've replaced but it still happens). An independent mechanic confirmed what the dealership told us.

When you get gas, you need to crank the cap well past the first click. The light still goes on sometimes, but typically after the next tank of gas and a few good turns of the cap, it eventially goes out. I hope this helps.