Circuit Description
The exhaust gas recirculation (EGR) solenoid and pintle valve assembly serve to reduce the temperature of combustion by introducing non-volatile exhaust gas into the combustion chambers. The EGR sensor signal voltage is constantly monitored. This circuit is bounded by upper and lower thresholds near 5 volts and zero volts. The voltage should never exceed the upper threshold, or be below the bottom threshold for correct operation. This DTC will set if the sensor signal voltage is lower than the lower threshold for longer than 1 second.
DTC Parameters
DTC P0405 will set if the EGR feedback signal is lower than 0.14 volts when:
| • | Condition exists for longer than 1 second |
| • | Engine is running |
| • | No battery voltage codes set |
Important: When this DTC sets, some EGR functions will be disabled for the remainder of that ignition cycle. When repairs are complete, codes must be cleared and ignition keyed Off for at least 10 seconds to allow proper operation.
P0405 is a (type B) DTC.
Diagnostic Aids
To locate an intermittent problem, use the scan tool to monitor the actual EGR position with engine running.
Wiggling wires while monitoring the actual EGR position may locate the area where a short to ground exists.
