P109D Code: Meaning, Causes, and Symptoms | OBD2 Codes

P109D – Short in Fuel Pressure Switching Valve Circuit

 

P109D Possible Symptoms

 

Engine Light ON (or Service Engine Soon Warning Light)

 

P109D Possible Causes

 

Faulty Fuel Pressure Switching Valve,Fuel Pressure Switching Valve harness is open or shorted,Fuel Pressure Switching Valve circuit poor electrical connection,Faulty F/PMP VSV relay,Faulty Engine Control Module (ECM)

 

P109D Description

 

A Flexible Fuel Vehicle (FFV) can be used with a fuel containing a high concentration of ethyl alcohol. This FFV uses a fuel pressure switching system which changes the fuel pressure to low or high using a fuel pressure switching valve. The code is stored when a malfunction is detected in the fuel pressure switching valve circuit. If the voltage of the fuel pressure switching valve circuit is different from the voltage commanded by the Engine Control Module (ECM), the ECM determines that the fuel pressure switching valve circuit is open or shorted, and stores a DTC.