P0640 Acura Manifold Intake Air Heater
– Intake Air Heater harness is open or shorted
– Intake Air Heater circuit poor electrical connection
The intake air (IA) heater is located in the air inlet tube and is used to warm the incoming air to aid in starting the engine and for proper cylinder combustion. The glow plug control module (GPCM) will command the IA heater ON when the engine coolant temperature is below 40 C (104 F). The power to the IA heater is supplied by the battery positive voltage circuit.
Acura Vehicle:
Acura ILX, Acura MDX, Acura RDX, Acura RLX, Acura TL, Acura TSX, Acura ZDX, Acura CSX, Acura EL, Acura Integra, Acura RSX, Acura Legend, Acura Vigor, Acura CL, Acura SLX, Acura NSX, Acura RL, Acura ZDX