P0338 - GLOW PLUGS/HEATER “A” CIRCUIT MALFUNCTION
DTC Code P0338 General Description The electric plug spark plugs are designed to heat up the combustion chamber, making it easier to start the engine at low temperatures. These plugs get hot before and during start-up. Afterwards , they remain open to avoid engine failure until the ideal temperature for good performance is reached. This process reduces pollutant gas emissions and smoke levels when the engine is cold. The engine control module (ECM) controls the heater plug by monitoring the coolant temperature and heater plug voltage. The heater system has eight separate power circuits between the controller and the heater plug. If the feedback voltage from the controller to the engine control module ( ECM ) is out of range, DTC code P0338 is set. Fault code P0338 General symptoms Check that the engine indicator light is illuminated. The engine is difficult to start, especially at low temperatures. Causes for OBD2 code P0338 General Code P0338 may be caused by one or mor