P2609 – Intake Air Heater System Performance

P2609 Possible Symptoms

Engine Light ON (or Service Engine Soon Warning Light)

P2609 Possible Causes

Faulty Intake Air Heater (IAH) Relay,Faulty Intake Air Heater,Intake Air Heater Relay harness is open or shorted,Intake Air Heater Relay circuit poor electrical connection,Intake Air Heater harness is open or shorted,Intake Air Heater circuit poor electrical connection

P2609 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. The control module will command the IAH ON when the engine coolant temperature is below 40 C (104 F). The power to the IAH heater is supplied by the battery positive voltage circuit through the IAH relay.