I have an 89 LX Convertible with no heat. I suspect something between the temperature control selector and the heater blend door. Is this a mechanical switch or vacuum actuated? If it's mechanical, I would suspect the switch, cable, or a linkage along the way. If vacuum, I'd probably test to make sure vacuum was getting supplied to the right place. And yes, I have considered the thermostat and or hoses, but they were all replaced last spring. Could this be a water pump problem? If so, would it be the only symptom?
Any thoughts are appreciated.