P0452
COMPONENT LOCATION
GENERAL DESCRIPTION
The evaporative emission control system prevents hydrocarbon vapors from escaping from the fuel tank into the atmosphere where they could form photochemical smog. Gasoline vapors are collected in the charcoal canister. The Fuel Tank Pressure Sensor (FTPS) is an integral part of the evaporative monitoring system. The ECM monitors the FTPS signal to detect vacuum decay and excess vacuum. The FTPS measures the difference between the air pressure inside the fuel tank and outside air pressure to check the purge control solenoid valve operation and for leak detection in the evaporative emission control system by monitoring pressure and vacuum levels in the fuel tank during the purge control solenoid valve operating cycles.
DTC DESCRIPTION
The fuel tank pressure sensor diagnostic will detect a fuel tank pressure sensor signal that is outof range or malfunctioning. The Tank Pressure Sensor Circuit Diagnostic compares the sensor input voltage to low and high limits. When the analog voltage is outside the allowable limits, the circuit is determined to be failed.
Checking output signals of tank pressure under detecting condition, if the tank pressure is low than 2V PCM sets P0452. MIL(Malfunction Indicatin Lamp) turns on when the malfunction lasts till cosecutive 2 driving cycle.
DTC DETECTING CONDITION
SPECIFICATION
SCHEMATIC DIAGRAM
MONITOR DTC STATUS
1. Connect scantool to Data Link Connector(DLC).
2. IG "ON".
3. Select "Diagnostic Trouble Codes(DTCs)" mode, and then Press F4(DTAL) to check DTC's information from the DTCs menu
4. Read "DTC Status" parameter.
5. Is parameter displayed "Present fault"?
YES
> Go to "Inspection & Repair" procedure.
NO
> Fault is intermittent, go to "Verification of vehicle Repair" procedure.
TERMINAL AND CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?
YES
> Repair as necessary and go to "Verification of Vehicle Repair" procedure
NO
> Go to " Power Circuit Inspection " procedure.
POWER CIRCUIT INSPECTION
1. IG "OFF" and disconnect FTPS connector.
2. IG "ON" & ENG "OFF"
3. Measure voltage between terminal 1 of FTPS harness connector and chassis ground.
Specification : Approx. 5V
4. Is the measured voltage within specification ?
YES
> Go to "Ground circuit inspection" procedure.
NO
> Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
SIGNAL CIRCUIT INSPECTION
1. Check voltage.
(1) IG "OFF" and disconnect FTPS connector.
(2) IG "ON" & ENG "OFF"
(3) Measure voltage between terminal 2 of FTPS harness connector and chassis ground.
Specification : Approx. 0V
(4) Is the measured voltage within specification ?
YES
> Go to "Check open in harness" as follows.
NO
> Repair short to ground in harness and go to "Verification of Vehicle Repair" procedure.
2. Check open in harness.
(1) IG "OFF" and disconnet FTPS and PCM connector.
(2) Measure resistance between terminal 2 of FTPS harness connector and terminal 28/C201-1 of PCM harness connector.
Specification : Approx. Below 1Ohms
(3) Is the measured resistance within specification ?
YES
> Go to "Component Inspection" procedure.
NO
> Repair open in harness and go to "Verification of Vehicle Repair" procedure.
COMPONENT INSPECTION
1. Check FTPS.
(1) IG "OFF" and connect scatool to DLC(Data Link Connector).
(2) Monitor "FTPS" parameter with accelleration on service data.
Specification
(3) Does the "FTPS" parameter with accelleraton on the service data change ?
YES
> Go to "Check PCM" as follows.
NO
> Substitute with a known - good FTPS and check for proper operation.
> If the problem is corrected, replace FTPS and go to "Verification of Vehicle Repair" procedure.
2. Check PCM.
(1) IG "OFF" disconnect FTPS connector
(2) Connect Scantool and IG "ON" & ENG "OFF"
(3) Select simulation function on scantool.
(4) Simulate voltage at terminal 2 of FTPS harness connector.
(5) Does the signal value of FTP sensor change according to simulation voltage ?
YES
> Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
NO
> Substitute with a known - good PCM and check for proper operation.
If the problem is corrected, replace PCM and go to "Verification of Vehicle Repair" procedure.
NOTE:
There is a memory reset function on scantool that can erase optional parts automatically detected and memorized by PCM
Before or after testing PCM on the vehicle, use this function to reuse the PCM on the others
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode.
2. Press F4(DTAL) and confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions.
3. Read "DTC Status" parameter.
4. Is parameter displayed "History(Not Present) fault"?
YES
> System performing to specification at this time. Clear the DTC
NO
> Go to the applicable troubleshooting procedure.