DTC P0403: EGR Solenoid Circuit

NOTE: For connector terminal ID, see CONNECTOR IDENTIFICATION . For wiring diagram, see WIRING DIAGRAMS article.

NOTE: EGR solenoid operation is monitored when ignition is on, engine is running and battery voltage is more than 10 volts. DTC may be stored in Powertrain Control Module (PCM) if EGR solenoid control circuit is not in the expected state when requested to operate by PCM. Possible causes are: defective EGR solenoid, defective PCM, or defective connectors or wiring.

Turn ignition on with engine off. Using scan tool, check for DTCs. If GLOBAL GOOD TRIP counter is displayed and equal to zero, go to next step. If GLOBAL GOOD TRIP counter is not displayed and equal to zero, go to step 8 .
Turn ignition off. Disconnect EGR solenoid connector. EGR solenoid contains a 2-pin connector and is located on top of EGR backpressure transducer and contains vacuum hose to EGR valve. See Figure .
Turn ignition on with engine off. Using scan tool, actuate EGR solenoid. Using voltmeter, check voltage at terminal No. 2 (White/Black wire) on EGR solenoid connector. If voltage is more than 10 volts, go to next step. If voltage is less than 10 volts, repair open on White/Black wire to EGR solenoid. White/Black wire is the fused ignition switch output which supplies voltage to EGR solenoid from ignition switch, through Positive Temperature Coefficient (PTC) No. 1, to power distribution center, and then to EGR solenoid. PTC No. 1 is a specified amperage solid-state circuit breaker which receives voltage when ignition is on and may be reset when all current is removed from PTC for approximately 20 seconds. PTC No. 1 is located in junction block behind driver's side of instrument panel, to left of steering column. Perform TEST VER-2A .
Turn ignition off. Using ohmmeter, check resistance between electrical terminals on EGR solenoid. If resistance is 25-50 ohms, go to next step. If resistance is not 25-50 ohms, replace EGR solenoid. Perform TEST VER-2A .
Ensure ignition is off. Disconnect PCM connectors. PCM is located between driver's side front fender and power distribution center, near battery.
Using ohmmeter, check resistance between terminal No. 1 (Gray/Yellow wire) on EGR solenoid connector and terminal No. 40 (Gray/Yellow wire) on Black PCM connector C1. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open on Gray/Yellow wire between PCM and EGR solenoid. Perform TEST VER-2A .
Ensure EGR solenoid and PCM connectors are still disconnected. Using ohmmeter, check resistance between ground and terminal No. 1 (Gray/Yellow wire) on EGR solenoid connector. If resistance is 5 ohms or more, replace PCM. Perform TEST VER-2A . If resistance is less than 5 ohms, repair short to ground on Gray/Yellow wire between PCM and EGR solenoid. Perform TEST VER-2A .
Turn ignition on with engine off. Using scan tool, actuate EGR solenoid. Feel for actuating operation at EGR solenoid while wiggling wiring harness and connectors between EGR solenoid and PCM. EGR solenoid contains a 2-pin connector and is located on top of EGR backpressure transducer and contains vacuum hose to EGR valve. See Figure . PCM is located between driver's side front fender and power distribution center, near battery.
If EGR solenoid does not stop operating while wiggling wiring harness and connectors, go to next step. If EGR solenoid stops operating while wiggling wiring harness and connectors, repair wiring or connectors between EGR solenoid and PCM as necessary that caused EGR solenoid to stop operating. Perform TEST VER-2A .
Turn ignition off. Inspect wiring harness and connectors between EGR solenoid and PCM. If no problems exist, test is complete. If any problems exist, repair wiring or connectors as necessary. Perform TEST VER-2A .