EPR Solenoid Electrical Check
EPR solenoid controls vacuum to EPR valve. The EPR solenoid, when energized, allows vacuum pump vacuum to close EPR valve and increase exhaust back pressure for proper EGR operation. Solenoid power (12V) is supplied by the ignition and grounded through the ECM, energizing the solenoid and turning EPR on.
NOTE:
The following step numbers refer to the numbers in the accompanying flow chart(s).
- Checks for short to ground or faulty ECM signal to solenoid. Test light should be off.
- Checks for signal to energize EPR solenoid with engine idling. If test light is on, electrical circuits to solenoid are OK.
- Checks for ignition voltage or open circuit from terminal "B" to ECM, terminal "C12".