Evaporative Emission Ventilation Switch or Mechanical Fault

Code Number
Scan tool 184
General scan tool P1494
MIL 31

Description
Evaporative Emission Ventilation Switch or Mechanical Fault

Probable Cause
- Evaporative emission ventilation solenoid failed
- Open or short circuit
- Vacuum hose clogged
- PCM failed

Background
- When the solenoid diaphragm moves up and down by activating the evaporative emission solenoid, the solenoid switch turns on and off.
- The PCM detects how often the solenoid is activated by counting the ON and OFF conditions of the solenoid switch.

Set Condition
- The solenoid is activated, but the solenoid switch does not turn on and off.





Diagnosis