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DTC P04EC-00: Evaporative emission purge system large leakage fuel tank side
 
 
 
 
CIRCUIT OPERATION
  • MFI relay is built into the IPDM E/R.
  • Power is supplied to the Evaporative Leak Check Module (ELCM) and evaporative emission purge solenoid from the MFI relay.
 
 
TECHNICAL DESCRIPTION
  • During the key-off evaporative leakage monitoring, by comparing the reference pressure for which the reference space in the ELCM with the reference orifice is depressurized and the value for which the evaporative emission system is depressurized, detect the leak in the evaporative emission system.
  • Determine whether it is a 0.5 mm (0.02 inch) leak or gross leak according to the depressurized value of the evaporative emission system.
  • By opening/closing the fuel tank solenoid valve and bypass valve, identify the leak on the fuel tank side and evaporative emission canister side.
 
 
DESCRIPTIONS OF MONITOR METHODS
Evaporative leak check monitor is performed by ELCM operation during key-off – after 5 to 8.5 hour soak. ECM makes a comparison between evapo system negative pressure and 0.5 mm (0.02 inch) leak negative pressure.
 
 
MONITOR EXECUTION
Once per driving cycle.
 
 
MONITOR EXECUTION CONDITIONS (OTHER MONITOR AND SENSOR)
Other Monitor (There is no temporary DTC set in memory for the item monitored below)
  • Evaporative emission purge solenoid monitor
  • Bypass valve monitor
  • Fuel tank solenoid valve monitor
  • Switching valve monitor
  • Canister pressure sensor monitor
  • Manifold absolute pressure sensor monitor
  • Fuel tank pressure sensor monitor
  • Fuel tank differential pressure sensor monitor
  • Barometric pressure sensor/Manifold absolute pressure correlation
  • Barometric pressure sensor monitor
  • Fuel level sensor monitor
  • Engine off timer monitor
  • Controller area network (CAN) monitor
Sensor (The sensors below are determined to be normal)
  • Engine coolant temperature sensor
  • Intake air temperature sensor
 
 
DTC SET CONDITIONS
Logic Flow Chart (Monitor Sequence)
Check Conditions
  • Power supply mode of electric motor switch is OFF.
  • 12V battery positive voltage is 11.0 volts or higher.
  • Engine coolant temperature is higher than 4°C (39°F) and lower than 35°C (95°F).
  • Intake air temperature at ECM wake-up is higher than 4°C (39°F) and lower than 35°C (95°F).
  • ECM is woken up in 5, 6 or 8.5 hours since the power supply mode of electric motor switch was OFF.
  • Barometric pressure is 76 kPa (22.4 in.Hg) or higher.
  • Fuel level is 85 percent or less.
  • Fuel tank pressure at ECM wake-up is less than 19.96 kPa (5.89 in.Hg) or more than 40.00 kPa (11.81 in.Hg).
  • Accumulated time that power supply mode of electric motor switch is ON is more than 27 minutes.
Judgment Criteria
  • The evaporative purge system leakage check pressure subtracted from the barometric pressure is following pressure or less: the barometric pressure – the second reference pressure in parentheses times 0.2.
  • The canister leakage check pressure subtracted from the barometric pressure is following pressure or more: the third reference pressure subtracted from the barometric pressure.
    or
  • The ratio of canister pressure with bypass valve closed to canister pressure with bypass valve open is specified value or higher.
  • The canister pressure subtracted from the barometric pressure is specified value or higher while the bypass valve is closed.
 
 
FAIL-SAFE AND BACKUP FUNCTION
None.
 
 
OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function, OBD-II Drive Cycle – Pattern 4 OBD- II DRIVE CYCLE.
 
 
TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CODE TO BE SET ARE:)
  • Fuel tank seal failed.
  • Purge line or vapor line seal failed.
  • Purge line is clogged.
  • ELCM circuit harness damage or connector damage.
  • Evaporative emission purge solenoid circuit harness damage or connector damage.
  • ECM failed.
 
 
DIAGNOSIS
Required Special Tools:
  • MB992744: Vehicle communication interface-Lite (V.C.I.-Lite)
  • MB992745: V.C.I.-Lite main harness A
  • MB992747: V.C.I.-Lite USB cable short
  • MB992748: V.C.I.-Lite USB cable long
1.STEP 1. Using scan tool (M.U.T.-III SE), check the data list.
Use scan tool (M.U.T.-III SE) to check the data list (Refer to DATA LIST REFERENCE TABLE).
  • Item number 540: EVP leak from tank NG
Q: Is the check result normal?
 
2.STEP 2. Check harness between IPDM E/R connector terminal number 78 and ELCM connector terminal number 8.
Check power supply line for damage.
Q: Is the check result normal?
Repair or replace the connector, or repair the damaged harness wire.
 
3.STEP 3. Check harness between ELCM connector terminal number 2 and ECM connector terminal number 93, check harness between ELCM connector terminal number 4 and ECM connector terminal number 80, check harness between ELCM connector terminal number 5 and ECM connector terminal number 117, check harness between ELCM connector terminal number 6 and ECM connector terminal number 107, and check harness between ELCM connector terminal number 7 and ECM connector terminal number 97.
Check signal line for damage.
Q: Are the check result normal?
Repair or replace the connector, or repair the damaged harness wire.
 
4.STEP 4. Check harness between ELCM connector terminal number 1 and ground.
Check ground line for damage.
Q: Is the check result normal?
Repair or replace the connector, or repair the damaged harness wire.
 
5.STEP 5. Check harness between IPDM E/R connector terminal number 66 and evaporative emission purge solenoid connector terminal number 2.
Check power supply line for damage.
Q: Is the check result normal?
Repair or replace the connector, or repair the damaged harness wire.
 
6.STEP 6. Check harness between evaporative emission purge solenoid connector terminal number 1 and ECM connector terminal number 14.
Check output line for damage.
Q: Is the check result normal?
Repair or replace the connector, or repair the damaged harness wire.
 
7.STEP 7. Check the evaporative emission purge solenoid for leaks.
Check evaporative emission purge solenoid itself (Refer to ENGINE, Engine, Motor and Emission Control – Emission Control – Evaporative Emission System EVAPORATIVE EMISSION PURGE SOLENOID CHECK).
Q: Does the evaporative emission purge solenoid hold pressure?
Replace the evaporative emission purge solenoid (Refer to ENGINE, Intake and Exhaust – Intake Manifold INTAKE MANIFOLD REMOVAL AND INSTALLATION).
 
8.STEP 8. Check for leaks in hose A, hose B and hose C.
Use a hand vacuum pump to check hose A, hose B and hose C.
Q: Does the hoses hold vacuum?
Replace any damaged hose.
 
9.STEP 9. Check for leaks in tube D and tube E.
Use a hand vacuum pump to check tube D and tube E.
Q: Does the tubes hold vacuum?
Replace any damaged tube.
 
10.STEP 10. Check the fuel tank solenoid valve for leaks.
Check fuel tank solenoid valve itself (Refer to ENGINE, Engine, Motor and Emission Control – Emission Control – Evaporative Emission System FUEL TANK SOLENOID VALVE CHECK).
Q: Does the fuel tank solenoid valve hold pressure?
Replace the fuel tank solenoid valve (Refer to ENGINE, Engine, Motor and Emission Control – Emission Control – Evaporative Emission System FUEL TANK SOLENOID VALVE REPLACEMENT).
 
11.STEP 11. Check for leaks in tube F and tube G.
(1) Drain the fuel from the fuel tank.
(2) Use a hand vacuum pump to check each tube F and tube G.
Q: Does the tubes hold vacuum?
Replace any damaged tube.
 
12.STEP 12. Check for leaks in tube H, tube I and evaporative emission (sub).
Use a hand vacuum pump to check each tube H, tube I and evaporative emission (sub).
Q: Does the tubes and evaporative emission (sub) hold vacuum?
Replace any damaged tube or evaporative emission (sub).
 
13.STEP 13. Check for leaks in the fuel tank.
Check for leaks in the fuel tank (Refer to ENGINE, Fuel Supply – On-vehicle Service FUEL LEAK CHECK OF FUEL TANK).
Q: Are any leaks found?
<When there is a leak from the attachment points of the fuel pump module, fuel tank differential pressure sensor, fuel level sensor or levelling valve>Repair or replace the leaked parts and check again that there are no leaks.
<When there is a leak from the fuel tank>Replace the fuel tank (Refer to ENGINE, Fuel Supply – Fuel Tank FUEL TANK REMOVAL AND INSTALLATION).
Replace the evaporative emission (main) (Refer to ENGINE, Engine, Motor and Emission Control – Emission Control – Evaporative Emission System EVAPORATIVE EMISSION CANISTER REMOVAL AND INSTALLATION). Then
 
14.STEP 14. Using scan tool (M.U.T.-III SE) to check the data list, after perform the evaporative emission system monitor test.
(1) Perform the evaporative emission system monitor test (Refer to EVAPORATIVE EMISSION CONTROL SYSTEM MONITOR TEST).
(2) Use scan tool (M.U.T.-III SE) to check the data list (Refer to DATA LIST REFERENCE TABLE).
  • Item number 540: EVP leak from tank NG
Q: Is the check result normal?
Intermittent malfunction (Refer to GENERAL INFORMATION, General Information – How to Use Troubleshooting/Inspection Service Points – How to Cope with Intermittent Malfunctions HOW TO COPE WITH INTERMITTENT MALFUNCTIONS).
Replace the ECM (Refer to ENGINE CONTROL MODULE (ECM) REMOVAL AND INSTALLATION).