What would cause the heater not to work in a 1996 Ford Aspire?

In a 1996 Ford Aspire, the heater may not work due to several potential issues. A common cause is low coolant levels, which can prevent proper heating. Additionally, a malfunctioning thermostat, a clogged heater core, or a faulty heater control valve could also disrupt the heating system. Lastly, issues with the blower motor or electrical connections may prevent warm air from circulating effectively.