EPR Solenoid Electrical Check
The EPR solenoid controls vacuum to EPR valve. The EPR solenoid, when energized, allows vacuum pump vacuum to close EPR valve and increase exhaust backpressure for proper EGR operation at idle. The solenoid is supplied 12 volts by the ignition and the ECM completes the ground to energize the solenoid and turn the EPR solenoid on.
NOTE:
The following step numbers refer to the numbers in the accompanying flow chart(s).
- This step checks for a short to ground or a faulty ECM signal to the EPR solenoid. The test light should be off.
- This checks for signal to energize the EPR solenoid with engine at idle. If test light is on, electrical circuits to EPR solenoid are okay.