P1404

Diagnostic Chart:

Schematic:

The Exhaust Gas Recirculation (EGR) valve consists of a pintle valve which moves by the use of an internal solenoid and an internal position sensor (potentiometer) used to determine pintle valve position. The PCM controls the solenoid by supplying it ignition voltage whenever exhaust gas needs to be recirculated into the intake manifold. The PCM monitors the EGR solenoid and position sensor circuits for correct voltage levels at certain times. The PCM will also monitor the position of the sensor in relation to its duty cycle (commanded On-time). DTC P1404 sets when the EGR sensor signal voltage is above the calibrated voltage value when the valve is commanded closed.

DTC PARAMETERS
DTC P1404 will set if:

Actual EGR position is greater than 4% when:
^ Commanded EGR position = 0%
^ Condition exists for longer than 20 seconds
^ Engine speed is less than 5000 rpm
^ EGR valve has been commanded to cycle greater than 61% four times
^ Ignition voltage is greater than 11 volts

OR

Actual EGR position is greater than 7.8 % when:
^ Commanded EGR position = 0%
^ Condition exists for longer than 20 seconds
^ Engine speed is greater than 5000 rpm
^ EGR valve has been commanded to cycle greater than 61% four times
^ Ignition voltage is greater than 11 volts

DTC P1404 diagnostic runs continuously once the above conditions have been met and the engine is running.

DTC P1404 is a type A DTC.

DIAGNOSTIC AIDS
If DTC P0403 or P1403 is set, diagnose that DTC first. A diagnosed EGR solenoid fault will cause this DTC to set.

Use Scan tool to command EGR SOLENOID On (PWM), while monitoring EGR SENSOR. The values for EGR SENSOR at a commanded state of 0% and 70% should fall within these ranges:

0% commanded state = 0.5-1.0 volts from EGR SENSOR.

70% commanded state = 4.2-4.7 volts from EGR SENSOR.

An open in circuit 452 or short to voltage on circuit 1456 will set this DTC.

Debris or binding pintle shaft holding EGR valve open may also set this DTC.