Faulty Exhaust Gas Recirculation (EGR) Cooler Bypass Valve
Exhaust Gas Recirculation Cooler Bypass Valve harness is open or shorted
Exhaust Gas Recirculation Cooler Bypass Valve circuit poor electrical connection
Faulty Engine Control Module (ECM)
Engine Light ON (or Service Engine Soon Warning Light)
Code P2494 Buick Description
The Engine Control Module (ECM) uses the Exhaust Gas Recirculation (EGR) cooler bypass valve position sensor to determine the position of the bypass valve. The ECM sends a reference voltage through the 5-volt reference circuit to the position sensor. The ECM provides a voltage return path for the sensor through the low reference circuit. A variable voltage signal, based on the bypass valve position, is sent from the sensor to the ECM through the position sensor signal circuit. The Diagnostic Trouble Code (DTC) will be set when the ECM detects that the EGR position sensor voltage is less than a calibrated threshold.
P2494 Buick Code – Exhaust Gas Recirculation Cooler Bypass Position Sensor Circuit Low Voltage