P0640 Cadillac Manifold Intake Air Heater
Possible causes
– Faulty Intake Air Heater
– Intake Air Heater harness is open or shorted
– Intake Air Heater circuit poor electrical connection
– Intake Air Heater harness is open or shorted
– Intake Air Heater circuit poor electrical connection
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P0640 Cadillac Description
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.
Cadillac Vehicle:Cadillac CTS Coupe, Cadillac CTS-V Coupe , Cadillac Eldorado , Cadillac Escalade EXT , Cadillac ATS , Cadillac CTS , Cadillac CTS Sedan , Cadillac CTS Sport Sedan , Cadillac CTS-V , Cadillac CTS-V Sedan , Cadillac Catera , Cadillac DTS , Cadillac DeVille , Cadillac STS-V , Cadillac STS , Cadillac Seville , Cadillac XTS , Cadillac XLR , Cadillac XLR Platinum , Cadillac Escalade , Cadillac SRX