The 2nd Gen has a rear heater core, so several possibilities. I assume the fan is working? If that's the case you could have a plugged rear heater core, a failed hot water valve not allowing flow to the core, or a failed mix door not allowing air to flow through the rear heater core. Maybe another thing or two I'm not thinking of.
2007 MDX Tech Billet Silver
2007 Honda Odyssey EX-L Nav/Res
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