DTC P1442 - EVAP System Vacuum Switch Circuit

Perform On-Board Diagnostic (OBD) System Check. See BASIC TESTING article. After performing OBD system check, go to next step.
Turn ignition on, with engine off, observe the "EVAP Vacuum Sw." display on the scan tool. If the "EVAP Vacuum Sw." displays "No Purge", go to next step. If "No Purge" is not displayed, go to step 4 .
Turn ignition on, with engine off, review and record scan tool Failure Records data. Operate the vehicle within Failure Records conditions as noted. Using the scan tool, monitor "Status this Ignition" for DTC P1442. If the scan tool indicates P1442 failed, go to next step. If P1442 does not fail, check for poor connection at PCM or damaged harness.
Disconnect the EVAP purge vacuum switch electrical connector. Connect a jumper between the EVAP purge vacuum switch harness connector terminals. Observe the "EVAP Vacuum Sw." display on the scan tool. If the "EVAP Vacuum Sw." displays "No Purge", go to step 6 . If "EVAP Vacuum Sw.", does not display "No Purge", go to next step.
Check for an open or short to ground in the EVAP vacuum switch signal circuit between the EVAP vacuum switch and the PCM, an open EVAP vacuum switch ignition feed circuit or a poor EVAP vacuum switch signal circuit connection at the PCM. If a problem is found, verify repair, and repair as necessary. If no problem is found, go to step 7 .
Check for poor connection at the EVAP vacuum switch. If a problem is found, verify repair, replace the faulty terminal(s) as necessary. If no problem is found, go to step 8 .

NOTE: The replacement PCM must be programmed.

Replace the PCM. Verify repair.
Replace the EVAP vacuum switch. Verify repair.