P0452
AL: DTC P0452 - EVAPORATIVE EMISSION CONTROL SYSTEM PRESSURE SENSOR LOW INPUTDTC DETECTING CONDITION:
- Immediately at fault recognition
CAUTION: After repair or replacement of faulty parts, conduct CLEAR MEMORY MODE and INSPECTION MODE. Refer to How To Clear Diagnostic trouble Codes. Clearing Diagnostic Trouble Codes
WIRING DIAGRAM
10AL1: CHECK CURRENT DATA.
1. Turn ignition switch to OFF.
2. Remove fuel filler cap.
3. Install fuel filler cap.
4. Turn ignition switch to ON.
5. Read the data of fuel tank pressure sensor signal using Subaru Select Monitor or the OBD-II general scan tool.
NOTE:
- Subaru Select Monitor
For detailed operation procedure Refer to the "READ CURRENT DATA SHOWN ON DISPLAY FOR ENGINE". Refer to Normal Scan Data Values
- OBD-II general scan tool
For detailed operation procedures, Refer to the OBD-II General Scan Tool Instruction Manual.
CHECK: Is the value less than -2.8 kPa (-21.0 mmHg, -0.827 inHg)?
YES: Go to step 10AL2.
NO: Even if MIL lights up, the circuit has returned to a normal condition at this time.
10AL2: CHECK POWER SUPPLY TO FUEL TANK PRESSURE SENSOR.
Connector & Terminal (B136) No.15 (+) - Chassis ground (-):
Measure voltage between ECM connector and chassis ground.
CHECK: Is the voltage more than 4.5 V?
YES: Go to step 10AL4.
NO: Go to step 10AL3.
10AL3: CHECK POWER SUPPLY TO FUEL TANK PRESSURE SENSOR.
Connector & Terminal (B136) No.15 (+) - Chassis ground (-):
Measure voltage between ECM connector and chassis ground.
CHECK: Does the voltage change more than 4.5 Volt by shaking harness and connector of ECM while monitoring the value with voltage meter?
YES: Repair poor contact in ECM connector.
NO: Contact with Subaru of America (SOA) service.
NOTE: Inspection by Subaru of America's DTM is required, because probable cause is deterioration of multiple parts.
10AL4: CHECK INPUT SIGNAL FOR ECM.
Connector & Terminal (B136) No.12 (+) - Chassis ground (-):
Measure voltage between ECM and chassis ground.
CHECK: Is the voltage less than 0.2 V?
YES: Go to step 10AL6.
NO: Go to step 10AL5.
10AL5: CHECK INPUT SIGNAL FOR ECM. (USING SUBARU SELECT MONITOR.)
Read data of fuel tank pressure sensor signal using Subaru Select Monitor.
NOTE:
- Subaru Select Monitor
For detailed operation procedure, Refer to the "READ CURRENT DATA SHOWN ON DISPLAY FOR ENGINE". Refer to Normal Scan Data Values.
CHECK: Does the value change more than -2.8 kPa (-21.0 mmHg, -0.827 inHg) by shaking harness and connector of ECM while monitoring the value with Subaru Select Monitor?
YES: Repair poor contact in ECM connector.
NO: Go to step 10AL6.
10AL6: CHECK HARNESS BETWEEN ECM AND COUPLING CONNECTOR IN REAR WIRING HARNESS.
1. Turn ignition switch to OFF.
2. Remove rear seat cushion (Wagon).
3. Separate rear wiring harness and fuel tank cord.
4. Turn ignition switch to ON.
Connector & Terminal (R15) No.9 (+) - Chassis ground (-):
5. Measure voltage between rear wiring harness connector and chassis ground.
CHECK: Is the voltage more than 4.5 V?
YES: Go to step 10AL7.
NO: Repair harness and connector.
NOTE:
In this case, repair the following:
- Open circuit in harness between ECM and rear wiring harness connector (R15)
- Poor contact in coupling connector (B98)
10AL7: CHECK HARNESS BETWEEN ECM AND COUPLING CONNECTOR IN REAR WIRING HARNESS.
1. Turn ignition switch to OFF.
2. Disconnect connector from ECM.
Connector & Terminal (B136) No.16 - (R15) No.11:
3. Measure resistance of harness between ECM and rear wiring harness connector.
CHECK: Is the resistance less than 1 ohm?
YES: Go to step 10AL8.
NO: Repair harness and connector.
NOTE:
In this case, repair the following:
- Open circuit in harness between ECM and rear wiring harness connector (R15).
- Poor contact in coupling connector (B98).
10AL8: CHECK HARNESS BETWEEN ECM AND COUPLING CONNECTOR IN REAR WIRING HARNESS.
Connector & Terminal (R15) No.11 - Chassis Ground:
Measure resistance of harness between rear wiring harness connector and chassis ground.
CHECK: Is the resistance more than 500 Kohm?
YES: Go to step 10AL9.
NO: Repair ground short circuit in harness between ECM and rear wiring harness connector (R15).
10AL9: CHECK FUEL TANK CORD.
1. Disconnect connector from fuel tank pressure sensor.
Connector & Terminal (R57) No.9 - (R47) No.3:
2. Measure resistance of fuel tank cord.
CHECK: Is the resistance less than 1 ohm?
YES: Go to step 10AL10.
NO: Repair open circuit in fuel tank cord.
10AL10: CHECK FUEL TANK CORD.
Connector & Terminal (R57) No.10 - (R47) No.1:
Measure resistance of fuel tank cord.
CHECK: Is the resistance less than 1 ohm?
YES: Go to step 10AL11.
NO: Repair open circuit in fuel tank cord.
10AL11: CHECK FUEL TANK CORD.
Connector & Terminal (R47) No.2 - Chassis Ground:
Measure resistance of harness between fuel tank pressure sensor connector and chassis ground.
CHECK: Is the resistance more than 500 Kohm?
YES: Go to step 10AL12.
NO: Repair ground short circuit in fuel tank cord.
10AL12: CHECK POOR CONTACT.
Check poor contact in fuel tank pressure sensor connector.
CHECK: Is there poor contact in fuel tank pressure sensor connector?
YES: Repair poor contact in fuel tank pressure sensor connector.
NO: Replace fuel tank pressure sensor.