P0452-EVAP PRESSURE SWITCH STUCK CLOSED





For a complete wiring diagram Refer to Section 8W.



Possible Causes
EVAP PURGE HOSE/TUBE OBSTRUCTION
(K52) EVAP PURGE CONTROL CIRCUIT SHORTED TO GROUND
(K107) ESM SIGNAL CIRCUIT SHORTED TO GROUND
ESM SWITCH
EVAP PURGE SOLENOID
PCM

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).



Diagnostic Test

1. VEHICLE HISTORY AND SERVICE BULLETIN INVESTIGATION

Ignition on, engine not running.
With a scan tool, select View DTC(s) and record the related Freeze Frame data if any DTC(s) are present.
Whether or not any DTC(s) are Active you will want to check the following items which may assist in repairing the customer's complaint successfully.
Check the vehicle's repair history.
If the vehicle has a repair history that pertains to the customer's current complaint, review the repair.
Inspect the vehicle for any aftermarket accessories that may have been installed incorrectly.
Check for any service bulletin(s) related to the customer's complaint or DTC(s).
If a service bulletin applies, follow the instructions per the service bulletin.

Choose the following scenario that best applies.

The service bulletin repaired the customer's complaint.


A DTC is present, no service bulletins apply, or the service bulletin didn't repair the customer's complaint.

2. ACTIVE DTC

Start the engine.
Allow the engine to reach normal operating temperature.
With a scan tool, select View DTCs and record the related Freeze Frame data.
It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.

Is the DTC Active or Pending at this time?

Yes


No

3. ESIM SWITCH STATE

With a scan tool, select Data Display and view the ESIM Switch state.
Disconnect the purge hose from the EVAP canister.

Is the ESIM Switch state change from 'Closed' to 'Open' when the purge hose was disconnected?

Yes


No

4. EVAP PURGE HOSE/TUBE OBSTRUCTION

Turn the ignition off.
Inspect the Evap Purge hose/tube for proper routing and installation between the EVAP Purge Solenoid and the Fuel Tank and between the Fuel Tank and the Evap Purge Canister.
Make sure the hose/tube is not damaged or kinked and is free from any obstructions or blockage.

Were any problems found?

Yes


No

5. (K52) EVAP PURGE CONTROL CIRCUIT SHORTED TO GROUND



Disconnect the C3 PCM harness connector.
Measure the resistance between ground and the (K52) Evap Purge Control circuit in the EVAP Purge Solenoid harness connector.

Is the resistance below 100 ohms?

Yes


No

6. EVAP PURGE SOLENOID

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Evap Purge Solenoid and the Powertrain Control Module (PCM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Refer to any Technical Service Bulletins that may apply.

Were any problems found?

Yes


No

7. ESIM ASSEMBLY

With a scan tool, select Data Display and view the ESIM Switch state.
Disconnect the Evap System Monitor Switch electrical connector.

Does the ESIM Switch state change from CLOSED to OPEN when the switch is disconnected?

Yes


No

8. (K107) ESM SIGNAL CIRCUIT SHORTED TO GROUND



Turn the ignition off.
Disconnect the C3 PCM harness connector.
Measure the resistance between ground and the (K107) ESM Signal circuit in the ESIM Assembly harness connector.

Is the resistance below 100 ohms?

Yes


No

9. PCM

NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.


Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.

Were there any problems found?

Yes


No