Possible causes

– Faulty Fuel Lift Pump
– Fuel Lift Pump harness is open or shorted
– Fuel Lift Pump circuit poor electrical connection

When is the code detected?

The commanded signal to the fuel lift pump does not match the feedback signal

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)

P0629 DODGE Description

When the ignition switch is turned on The ECM will mobilize the fuel pump relay and run the in-tank fuel pump as soon as the ignition is switched ON. The fuel pump will function till the engine cranks or runs, and the ECM continues to obtain ignition reference pulses.