P0406

Wiring Diagram:

EGR Position Sensor Circuit High Voltage:

P0406- EGR POSITION SENSOR CIRCUIT HIGH VOLTAGE
The exhaust gas recirculation (EGR) value consists of a pintle valve that moves by the use of an internal solenoid and an internal position sensor (potentiometer) 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. The ECM monitors the EGR solenoid and position sensor circuit for correct voltage levels at certain times. Normal EGR sensor voltages range from 0.5-1.0 volts at a 0% commanded duty cycle up to 4.2-4.7 volts at a 100% commanded duty cycle. DTC P0406 sets when the EGR sensor signal voltage at the ECM is above the calibrated voltage value.

DTC PARAMETERS
DTC P0406 will set if the EGR sensor signal is above 4.82 volts when;
^ Condition exists for longer than 1 second
^ Engine is running
^ No system voltage DTCs set

DTC P0406 diagnostic runs continuously with engine running.

P0406 is type B DTC

DIAGNOSTIC AIDS
To locate an intermittent problem, use the Scan tool to monitor EGR SENSOR voltage with ignition On, engine Off.

Wiggling wires while monitoring EGR SENSOR may locate the area where an open or short to voltage in wiring may exist.

Circuit 416 (CMP/EGR/MAF/MAP sensor). circuit 2709 (AC pressure/fuel tank pressure sensor) and circuit 1164 (APP sensor 1) share the same 5 volt reference supply (5 volt Ref-A).

The CMP/ECT/IAT/EGR/MAF/MAP/TP1/TP2 sensors share the same sensor return circuit 652.

IMPORTANT: When DTC P0406 sets, some EGR functions will be disabled for the remainder of the ignition cycle. When repairs are complete. DTCs must be cleared and ignition turned Off for 10 seconds to allow proper EGR operation.