P0403

Description
EGR SOLENOID CONTROL CIRCUIT

PCM monitors EGR valve pintle position input to ensure that
valve responds properly to commands from PCM. The EGR (linear) valve
is controlled by using an ignition positive driver and ground circuit
within the PCM. The driver has the ability to detect an electrical
malfunction in the ignition positive or ground circuit, then signal
the PCM to set the DTC.
Symptoms
A fault in the control circuit, will leave no noticeable symptoms other than the Service Engine Soon (SES) light. If the EGR control solenoid is stuck open the code may be accompanied by misfire under acceleration, rough idle, or engine stalling.

Causes

• Bad EGR solenoid
• Resistance in control circuit (PCM controlled ground) due to damage to the wiring harness
• Poor connection at the EGR solenoid harness
• Corrosion at the EGR solenoid harness
• Stuck pintle

Possible Solutions

• Check wires and harness for shorts or loose connections.
• Remove EGR valve and clean pintle
• Replace EGR valve