GM Service Manual Online
For 1990-2009 cars only

SES Light and DTC P0230

Subject:SES Light and DTC P0230

Models:2004 - 2009 Passenger Cars and Light Duty Trucks
Equipped with gasoline engines



The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Some owners may comment that the Service Engine Soon (SES) light has illuminated. Upon closer inspection using a Tech 2, DTC P0230 (Fuel Pump Relay Control Circuit) may have been found stored in the PCM

Recommendation/Instructions:

Follow the appropriate diagnostic information in SI. If no cause for the DTC can be found, inspect the vehicle for installation of an aftermarket anti-theft system. Some aftermarket anti-theft systems may have features that take control of or override the fuel pump relay circuit. Anti-theft systems that have such features may cause the diagnostic code to set if an attempt is made to start the vehicle without first disabling (turning off) the aftermarket system.

If such an aftermarket system is found on the vehicle and the condition (setting the DTC) can be duplicated by not disabling the system prior to starting the vehicle, advise the vehicle owner that the cause of the SES light being illuminated is the aftermarket anti-theft system.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.