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DTC P0452: Evaporative Emission System Pressure Sensor Low Input
 
 
 
 
CIRCUIT OPERATION
  • The ECM terminal FDP5 supplies a 5 volts reference signal to the fuel tank differential pressure sensor. The fuel tank differential pressure sensor is grounded through the ECM terminal FDPE.
  • The fuel tank differential pressure sensor returns a voltage signal to the ECM terminal FDPS that is proportional to the pressure in the fuel tank.
 
 
TECHNICAL DESCRIPTION
  • The ECM monitors the fuel tank differential pressure sensor output voltage.
  • The ECM determines whether the fuel tank differential pressure sensor signal voltage is within normal operating parameters.
 
 
DESCRIPTIONS OF MONITOR METHODS
  • Fuel tank differential pressure sensor output voltage is out of specified range.
 
 
MONITOR EXECUTION
  • Continuous
 
 
MONITOR EXECUTION CONDITIONS (OTHER MONITOR AND SENSOR)
Other Monitor (There is no temporary DTC set in memory for the item monitored below)
  • Not applicable
Sensor (The sensors below are determined to be normal)
  • Not applicable
 
 
DTC SET CONDITIONS
Logic Flow Chart
Check Condition
  • More than 2 seconds have passed since the power supply mode of electric motor switch was ON.
Judgment Criterion
  • The fuel tank differential pressure sensor output voltage is less than 0.044 volt for 2 seconds.
 
 
FAIL-SAFE AND BACKUP FUNCTION
  • Fuel filler lid cannot be opened even when pressing the fuel filler lid opener switch.
  • Indicates "REFUELING SYSTEM SERVICE REQUIRED" on the information screen in the multi-information display.
 
 
OBD-II DRIVE CYCLE PATTERN
  • Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 1 .
 
 
TROUBLESHOOTING HINTS (THE MOST LIKELY CAUSES FOR THIS CODE TO BE SET ARE:)
  • Fuel tank differential pressure sensor failed.
  • Open or shorted fuel tank differential pressure sensor circuit, connector damage.
  • ECM failed.
 
 
DIAGNOSIS
Required Special Tool:
  • MB992110: Power Plant ECU Check Harness
STEP 1. Using scan tool (M.U.T.-IIISE), check data list item 210: Fuel Tank Differential Pressure Sensor.
cautionTo prevent damage to scan tool (M.U.T.-IIISE), always turn off the power supply mode of the electric motor switch before connecting or disconnecting scan tool (M.U.T.-IIISE).
(1) Connect scan tool (M.U.T.-IIISE). Refer to HOW TO CONNECT THE SCAN TOOL (M.U.T.-IIISE) .
(2) Turn on the power supply mode of the electric motor switch.
(3) Remove the fuel cap.
(4) Set scan tool (M.U.T.-IIISE) to the data reading mode for item 210, Fuel Tank Differential Pressure Sensor.
  • The standard value should be -0.57 to 0.57 kPa (-0.168 to 0.168 in.Hg).
(5) Install the fuel cap.
(6) Turn off the power supply mode of the electric motor switch.
Is the sensor operating properly?
It can be assumed that this malfunction is intermittent. Refer to GROUP 00, How to Use Troubleshooting / Inspection Service Points - How to Cope with Intermittent Malfunctions .
Go to Step 2.
 
STEP 2. Measure the sensor supply voltage at fuel tank differential pressure sensor connector.
(1) Disconnect the fuel tank differential pressure sensor connector and measure at the harness side.
(2) Turn on the power supply mode of the electric motor switch.
(3) Measure the voltage between terminal FDP5 line and ground.
  • Voltage should be between 4.9 and 5.1 volts.
(4) Turn off the power supply mode of the electric motor switch.
Is the measured voltage between 4.9 and 5.1 volts?
Go to Step 5.
Go to Step 3.
 
STEP 3. Measure the sensor supply voltage at ECM connector by using power plant ECU check harness special tool MB992110.
(1) Disconnect the fuel tank differential pressure sensor connector.
(2) Disconnect all ECM connectors. Connect the power plant ECU check harness special tool MB992110 between the separated connectors.
(3) Turn on the power supply mode of the electric motor switch.
(4) Measure the voltage between terminal FDP5 and ground.
  • Voltage should be between 4.9 and 5.1 volts.
(5) Turn off the power supply mode of the electric motor switch.
Is the measured voltage between 4.9 and 5.1 volts?
Repair or replace the connector(s), or check and repair the harness of open circuit in FDP5 line between fuel tank differential pressure sensor connector and ECM connector. Then go to Step 9.
Go to Step 4.
 
STEP 4. Check of short circuit to ground in FDP5 line between fuel tank differential pressure sensor connector and ECM connector.
Is the harness wire in good condition?
Go to Step 8.
Repair the connector(s) or wiring harness. Then go to Step 9.
 
STEP 5. Measure the sensor output voltage at ECM connector by using power plant ECU check harness special tool MB992110.
(1) Disconnect all ECM connectors. Connect the power plant ECU check harness special tool MB992110 between the separated connectors.
(2) Turn on the power supply mode of the electric motor switch.
(3) Remove the fuel cap
(4) Measure the voltage between terminal FDPS and ground.
  • Voltage should be between 1.5 and 3.5 volts.
(5) Turn off the power supply mode of the electric motor switch.
Is the measured voltage normal?
Go to Step 8.
Go to Step 6.
 
STEP 6. Check of short to ground and open circuit in FDPS line between fuel tank differential pressure sensor connector and ECM connector.
Is the harness wire in good condition?
Go to Step 7.
Repair the connector(s) or wiring harness. Then go to Step 9.
 
STEP 7. Replace the fuel tank differential pressure sensor.
(1) Replace the fuel tank differential pressure sensor.
(2) Carry out test drive with the drive cycle pattern. Refer to Diagnostic Function. OBD-II Drive Cycle. Pattern 1 .
(3) Check the diagnostic trouble code (DTC).
Is DTC P0452 set?
Replace the ECM (Refer to Removal and Installation ). Then go to Step 9.
The inspection is complete.
 
STEP 8. Using scan tool (M.U.T.-IIISE), check data list item 210: Fuel Tank Differential Pressure Sensor.
(1) Turn on the power supply mode of the electric motor switch.
(2) Remove the fuel cap.
(3) Set scan tool (M.U.T.-IIISE) to the data reading mode for item 210, Fuel Tank Differential Pressure Sensor.
  • The standard value should be -0.57 to 0.57 kPa (-0.168 to 0.168 in.Hg).
(4) Install the fuel cap.
(5) Turn off the power supply mode of the electric motor switch.
Is the sensor operating properly?
It can be assumed that this malfunction is intermittent. Refer to GROUP 00, How to Use Troubleshooting / Inspection Service Points - How to Cope with Intermittent Malfunctions .
Replace the ECM (Refer to Removal and Installation ). Then go to Step 9.
 
STEP 9. Perform the OBD-II drive cycle.
(1) Carry out a test drive with the drive cycle pattern. Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 1 .
(2) Check the diagnostic trouble code (DTC).
Is DTC P0452 set?
Retry the troubleshooting.
The inspection is complete.