P0543 Cadillac Intake Air Heater Incorrect Voltage
Possible causes
– Faulty Intake Air Heater relay
– Faulty Intake Air Heater
– Intake Air Heater harness is open or shorted
– Intake Air Heater circuit poor electrical connection
– Faulty Intake Air Heater
– Intake Air Heater harness is open or shorted
– Intake Air Heater circuit poor electrical connection
What about the obd code?
The Engine Control Module (ECM) sends a bias voltage on diagnostic circuits one and two. If this voltage is not pulled low when the relay is OFF, or is high with the relay ON, DTC P0543 Cadillac will set. The ECM will only store info on first failure, It triggers the SES light on the second failure.
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P0543 Cadillac Description
The Engine Control Module (ECM) uses an Intake Air Heater (IAH) to warm the incoming air for proper cylinder combustion. The ECM grounds the control coil of the IAH relay to energize the heater during cold operation.
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