P0542 OBD Code Definition:
P0542 Intake Air Heater Relay 1 High
P0542 OBD Code Description:

OBD Code P0542

Intake Air Heater “A” Circuit High

What’s mean?

OBD2 Code P0542 Definition:
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. The ECM sends a bias voltage on diagnostic circuits one and two.


Possible sumptoms of P0542
– Engine Light ON (or Service Engine Soon Warning Light)

Possible Causes

Possible causes of P0542
– Open or short intake air heater relay circuit condition – Intake air heater relay poor electrical connection – Faulty Intake Air Heater Relay The Error code is generally activated on detection of the following conditions: The P0542 code is detected when the Signal from the #1 intake air heater output does not match the signal input

Possible Solutions

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