P2478 CHEVROLET – Exhaust Gas Temperature Out of Range Bank 1 Sensor 1

P2478 CHEVROLET Possible Symptoms

Engine Light ON (or Service Engine Soon Warning Light)

P2478 CHEVROLET Possible Causes

Faulty Exhaust Gas Temperature Sensor (EGTS) Bank 1 Sensor 1,Exhaust Gas Temperature Sensor Bank 1 Sensor 1 harness is open or shorted,Exhaust Gas Temperature Sensor Bank 1 Sensor 1 circuit poor electrical connection,Exhaust leaks,Excessive particulate matter buildup on sensor

P2478 CHEVROLET Description

The Powertrain Control Module (PCM) continuously monitors the Exhaust Gas Temperature Sensor (EGTS) for proper circuit continuity and out of range high values. The EGTS is located in front of the Diesel Oxidation Catalyst (DOC) and/or in front of the Diesel Particulate Filter (DPF). The EGTS detects exhaust gas temperature and converts it into a voltage and feeds back to the PCM with the voltage signal in order to control engine conditions to effectively reduce emissions. The PCM sets the P2478 OBDII code when the Exhaust Gas Temperature Sensor is out of factory specifications.