U0118 Code: Meaning, Causes, and Symptoms | OBD2 Codes

U0118 – Lost Communication With Fuel Additive Control Module

 

U0118 Possible Symptoms

 

Engine Light ON (or Service Engine Soon Warning Light)

 

U0118 Possible Causes

 

Top Off Fuel Additive Tank,Faulty Fuel Additive Sensor,Faulty Fuel Additive Control Module,Fuel Additive Control Module harness is open or shorted,Fuel Additive Control Module circuit poor electrical connection

 

U0118 Description

 

The main purpose of the Fuel Additive Control Module is to calculate the required amount of fuel additive and control the time of injection into the fuel tank. It also stores Diagnostic Trouble Codes (DTC) for the fuel additive system. In addition to the already mentioned operation of the fuel additive system module, the instrument cluster will receive a command from the fuel additive system module to illuminate the Malfunction Indicator Lamp (MIL) or the Powertrain Control Module (PCM) warning indicator if there are concerns with the additive system or if the fuel additive tank requires refilling. The PCM will set the OBDII code when the PCM loses communication with the Fuel Additive Control Module.