P0403

Wiring Diagram:

EGR Solenoid Control Circuit:

P0403- EGR SOLENOID CONTROL CIRCUIT
The exhaust gas recirculation (EGR) value consists of a pintle valve which moves by the use of an internal solenoid and an internal position sensor (potentiometer) which used to determine pintle valve position. The ECM controls the solenoid by supplying it ground whenever exhaust gas needs to be recirculated into the intake manifold. When the solenoid is commanded Off (circuit not grounded) the voltage level at the ECM should be high (ignition voltage). When the solenoid is commanded On (circuit grounded), the voltage level at the ECM should be low. The ECM EGR solenoid feedback circuit uses a pull-up voltage (2.6-4.6 volts) which allows the ECM to individually differentiate between an open, short to ground or short to voltage. DTC P0403 will set if the ECM detects an open EGR solenoid control circuit when EGR solenoid is commanded Off with engine cranking/running.

DTC PARAMETERS
DTC P0403 will set if EGR solenoid feedback voltage is between 2 6 and 4.6 volts (ECM pull-up voltage indicating an open circuit) when EGR solenoid is commanded Off when:
^ Condition exists for longer than 0.5 seconds
^ Engine speed is greater than 40 rpm
^ Battery voltage is between 7.5 and 15.0 volts

DTC P0403 diagnostic runs continuously once the above conditions have been met.

P0403 is a type B DTC

DIAGNOSTIC AIDS
To locate an intermittent problem. use Scan tool to monitor DTC P0403 LAST TEST with engine running. Wiggling wires while watching for a change for PASSED to FAILED may locate the area where an open in the wiring may exist.

In order for circuit 251 to be the cause of DTC P0403, both 251 circuits at the ECM must be open.

EGR solenoid resistance; 7-11 ohms.