Service Repair Manual

GENERAL (FBC)
Cold Mixture Heater (CMH) Relay Control
System
The cold mixture heater is a Positive Temperature Coefficient
(PTC) heater installed between the carburetor and intake
manifold.
When the engine coolant temperature is below 60°C (140°F), the
ECU energizes the cold mixture heater relay. The closed relay
supplies voltage to the cold mixture heater. The cool air-fuel
mixture is heated and atomized by the heater before it reaches
the combustion chamber for improved combustion.
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