EGR Control Solenoid: Description and Operation

EGR Mounting:

Electric EGR Transducer (EET):

NOTE: The Electronic EGR Transducer (EET) assembly is a vacuum control solenoid and a backpressure transducer, in one package.

PURPOSE

The PCM controls when the EGR valve can be actuated, through the solenoid valve portion of the EET.

OPERATION

Ported vacuum from the throttle body, is supplied to the solenoid valve.

The PCM controls the flow of vacuum between the throttle body and the back pressure transducer, (through the solenoid ground circuit).

- When the solenoid is energized (grounded), no vacuum is supplied to the transducer.

- When the solenoid is de-energized (not grounded), vacuum is supplied to the transducer.

The solenoid will always be energized (no EGR), under following conditions:

- Engine warm-up, (engine coolant temperature below 40 ~F)
- Engine at idle
- Wide Open Throttle (WOT) operation
- Rapid acceleration/deceleration
- During EGR system diagnostic check

NOTE: If the wiring or connector is disconnected from the solenoid, the EGR valve will operate at all times, (adversely affecting engine idle and performance).

CIRCUIT OPERATION
Circuit F87 supplies battery voltage to the EGR solenoid. The Powertrain Control Module (PCM) switches the ground path for the solenoid ON and OFF on circuit K35. Circuit K35 connects to cavity 40 of the PCM.

In the START or RUN position, the ignition switch connects circuit Al from fuse 5 in the Power Distribution Center (PDC) to circuit A21. Circuit A21 feeds circuit F87 through the 9 amp positive temperature coefficient (PTC No.1) in the junction block.

Helpful Information
Circuit F87 splices to feed Torque Converter Clutch (TCC) solenoid, EVAP/Purge solenoid, PCM, and the coil side of the fuel pump relay.