Tried it, but no difference. Pressed and held both (mirror button and remote button) and the slow blinking yellow light never changed. It's as if the mirror button doesn't recognize the signal.

This is a brand-new remote control with a coin battery. Every time I press it, the door opens or closes reliably. Do I need to change the battery anyway?

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2008 ML350
2007 Honda Element
2007 Honda Accord
2009 Honda Civic