P0452
P0452-EVAP PRESSURE SWITCH STUCK CLOSED
For a complete wiring diagram, refer to the Wiring Information.
Theory of Operation
The Evaporative Purge Monitor tests the integrity of the hoses/tube between the throttle body/intake and the fuel tank. The monitor is a two stage test and runs only after the Evaporative system passes the small leak test. Stage one is non-intrusive. The Powertrain Control Module (PCM) monitors the purge vapor ratio and the Evaporative System Integrity Monitor (ESIM) switch closed ratio. If the purge vapor ratio is above a calculated value, the monitor passes. If the ESIM switch closed ratio is greater than calculated value when purge flow is greater than a minimum value, the monitor passes. Stage two is an intrusive test and runs only if stage one does not pass. The PCM commands the purge solenoid to flow at a specified rate to force the purge vapor ratio to update. The ratio is compared to a calibrated specification. If it is less than specified, a one trip failure is recorded. This test can detect if the purge hose is off, obstructed or the purge valve is not operational.
- When Monitored:
Immediately after the ignition has been turned off.
- Set Condition:
At key off, the Powertrain Control Module (PCM) energizes the Purge Solenoid for a calibrated amount of time (30 seconds maximum) and stores the state of the ESIM switch. The state is evaluated again at the next key on. If the PCM does not detect that the ESIM switch is open, an error is detected. Two Trip Fault. Three good trips to turn off the MIL.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
1. VEHICLE HISTORY AND SERVICE BULLETIN INVESTIGATION
1. Ignition on, engine not running.
2. With the scan tool, select View DTCs and record the related Freeze Frame data if any DTCs are present.
3. Whether or not any DTCs are Active you will want to check the following items which may assist in repairing the customer's complaint successfully.
4. Check the vehicles repair history.
5. If the vehicle has a repair history that pertains to the customer's current complaint, review the repair.
6. Inspect the vehicle for any aftermarket accessories that may have been installed incorrectly.
7. Check for any service bulletin(s) related to the customer's complaint or DTCs.
8. 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.
- Testing complete.
A DTC is present, no service bulletins apply or the service bulletin didn't repair the customer's complaint.
- Go To 2
2. ACTIVE DTC
NOTE: If the customer is experiencing an early fuel shut off during the fuel filling process along with P0440, P0441 and P0452 setting, you need to check for restrictions in the Evaporative Purge tubes/hoses as well as the Fresh Air Filter before continuing.
1. Ignition on, engine not running.
2. With the scan tool, select View DTCs.
Is the DTC Active at this time?
Yes
- Go To 3
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test.
3. ESIM SWITCH STATE
1. With the scan tool, select Data Display and view the ESIM switch state.
2. Disconnect the purge hose from the Evaporative canister.
Is the ESIM switch state change from 'Closed' to 'Open' when the purge hose was disconnected?
Yes
- Go To 4
No
- Go To 7
4. EVAPORATIVE PURGE HOSE/TUBE AND FRESH AIR FILTER OBSTRUCTION
1. Turn the ignition off.
2. Inspect the Evaporative 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.
3. Make sure the hose/tube and fresh air filter are not damaged, kinked and free from any obstructions.
4. Check for any kink in the purge line connecting the LPV (Linear Purge Valve) to intake manifold.
Were any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 5
5. (K52) EVAP PURGE CONTROL CIRCUIT SHORTED TO GROUND
1. Disconnect the C3 PCM harness connector.
2. 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
- Repair the short to ground in the (K52) Evap Purge Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Go To 6
6. EVAP PURGE SOLENOID
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Evap Purge Solenoid and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Evap Solenoid and the Powertrain Control Module connectors.
4. Perform any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Replace the Evap Purge Solenoid.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
7. ESIM ASSEMBLY
1. With the scan tool, select Data Display and view the ESIM switch state.
2. Disconnect the ESIM switch electrical connector.
Does the ESIM switch state change from CLOSED to OPEN when the switch is disconnected?
Yes
- Verify that there is good pin to terminal contact in the Switch and the Powertrain Control Module connectors. Replace the ESIM switch Assembly if no problems were found with the connectors.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
No
- Go To 8
8. (K107) ESIM SWITCH SIGNAL CIRCUIT SHORTED TO GROUND
1. Turn the ignition off.
2. Disconnect the C3 PCM harness connector.
3. Measure the resistance between ground and the (K107) ESIM switch Signal circuit in the ESIM Assembly harness connector.
Is the resistance below 100 Ohms?
Yes
- Repair the short to ground in the (K107) ESIM switch Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
No
- Go To 9
9. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Evap Purge Solenoid Assembly, ESIM switch and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the ESIM, Evap Purge Solenoid and the Powertrain Control Module connectors.
4. Perform any Technical Service Bulletins that may apply.
Were there any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Replace and program the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.