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DTC P1469: Abnormal Correlation Between Canister Pressure Sensor And Manifold Absolute Pressure Sensor
 
 
 
 
TECHNICAL DESCRIPTION
  • During the key-off evaporative leakage monitoring, compare the atmospheric pressures measured by the manifold absolute pressure sensor and canister pressure sensor, and when the difference is larger than the predetermined value, it is judged as a failure.
 
 
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)
  • 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 sensor below is determined to be normal)
  • Engine coolant temperature sensor
  • Intake air temperature sensor
 
 
DTC SET CONDITIONS
Logic Flow Chart
Check Conditions
  • Power supply mode of the electric motor switch is OFF.
  • 12V starter battery positive voltage is 11 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 % 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).
Judgment Criterion
  • Difference between manifold absolute pressure sensor output and canister pressure sensor output is more than 8.95 kPa (2.643 in.Hg) for 2 seconds.
 
 
FAIL-SAFE AND BACKUP FUNCTION
  • None.
 
 
OBD-II DRIVE CYCLE PATTERN
  • Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 4 .
 
 
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
  • Canister pressure sensor failed.
  • Manifold absolute pressure sensor failed.
  • Open or shorted canister pressure sensor circuit or connector damage.
  • ECM failed.

 
 
DIAGNOSIS
STEP 1. Using scan tool (M.U.T.-IIISE), read the diagnostic trouble code (DTC).
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) Read the DTC.
(4) Turn off the power supply mode of the electric motor switch.
Is the diagnostic trouble code other than P1469 set?
Refer to Diagnostic Trouble Code Chart .
Go to Step 2.
 
STEP 2. Using scan tool (M.U.T.-IIISE), check data list item 212: Canister Pressure Sensor.
(1) Turn on the power supply mode of the electric motor switch.
(2) Set scan tool (M.U.T.-IIISE) to the data reading mode for item 212, Canister Pressure Sensor.
  • When altitude is 0 m (0 foot), 101 kPa (29.8 in.Hg).
  • When altitude is 600 m (1,969 feet), 95 kPa (28.1 in.Hg).
  • When altitude is 1,200 m (3,937 feet), 88 kPa (26.0 in.Hg).
  • When altitude is 1,800 m (5,906 feet), 81 kPa (23.9 in.Hg).
(3) Turn off the power supply mode of the electric motor switch.
Is the sensor operating properly?
Go to Step 5.
Go to Step 3.
 
STEP 3. Measure the sensor supply voltage at evaporative leak check module harness side connector.
(1) Disconnect the evaporative leak check module 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 EVSS 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?
Refer to DTC P24B9 - Canister Pressure Sensor Noise , DTC P24BA - Canister Pressure Sensor Circuit Low Input , DTC P24BB - Canister Pressure Sensor Circuit High Input . Then go to Step 7.
Go to Step 4.
 
STEP 4. Check of short to ground and open circuit in EVSS line between evaporative leak check module connector and ECM connector.
Is the harness wire in good condition?
Go to Step 6.
Repair the connector(s) or wiring harness. Then go to Step 7.
 
STEP 5. Using scan tool (M.U.T.-IIISE), check data list item 8: Manifold Absolute Pressure Sensor.
(1) Turn on the power supply mode of the electric motor switch.
(2) Set scan tool (M.U.T.-IIISE) to the data reading mode for item 8, Manifold Absolute Pressure Sensor.
  • When altitude is 0 m (0 foot), 101 kPa (29.8 in.Hg).
  • When altitude is 600 m (1,969 feet), 95 kPa (28.1 in.Hg).
  • When altitude is 1,200 m (3,937 feet), 88 kPa (26.0 in.Hg).
  • When altitude is 1,800 m (5,906 feet), 81 kPa (23.9 in.Hg).
(3) Set the vehicle to the continuous idling mode, and warm up the engine.
  • The standard value should be 28.3 - 41.7 kPa (8.36 - 12.31 in.Hg).
  • When the engine is suddenly revved, manifold absolute pressure varies.
(4) Turn off the power supply mode of the electric motor switch.
Is the sensor operating properly?
Go to Step 6.
Refer to DTC P0106 - Manifold Absolute Pressure Circuit Range/Performance Problem , DTC P0107 - Manifold Absolute Pressure Circuit Low Input , DTC P0108 - Manifold Absolute Pressure Circuit High Input . Then go to Step 7.
 
STEP 6. Using scan tool (M.U.T.-IIISE), check the evaporative emission system monitor test
(1) Carry out an evaporative emission system monitor. Refer to Evaporative Emission System Monitor Test .
(2) Check the item 192, Canister SENS.-MAPS Correlation in the data list.
(3) Turn off the power supply mode of the electric motor switch.
Is the data list "Normal"?
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 7.
 
STEP 7. Test 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 4 .
(2) Check the diagnostic trouble code (DTC).
Is DTC P1469 set?
Retry the troubleshooting.
The inspection is complete.