P0452
P0452Component 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 PCM 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
Checking output signals of tank pressure under detecting condition, if the tank pressure is lower than threshold, PCM sets P0452. MIL (Malfunction Indication Lamp) turns on when the malfunction lasts till consecutive 2 driving cycle.
DTC Detecting Condition:
Specification:
Schematic Diagram:
Monitor Scantool Data
1. IG "OFF" & connect scantool.
2. ENG "ON" and warm-up the engine to normal operating temperature.
3. Monitor "FTPS" parameter on the service data.
4. Is the "FTPS" data displayed correctly?
YES - Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, ending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure
NO - Go to "Terminal and Connector Inspection" 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 Supply Circuit Inspection
1. IG "OFF" and disconnect FTPS connector.
2. IG "ON" and ENG "OFF"
3. Measure voltage between terminal 2 of FTPS harness connector and chassis ground.
Specification: Approx. 5 V
4. Is the measured voltage within specification?
YES - Go to "Signal 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 1 of FTPS harness connector and chassis ground.
Specification: Approx. 0 V
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 disconnect FTPS and PCM connector.
2. Measure resistance between terminal 1 of FTPS harness connector and terminal 28 of PCM harness connector.
Specification: Approx. Below 1 ohm
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 scan tool to DLC (Data Link Connector).
2. Monitor "FTPS" parameter with acceleration on service data.
Specification:
3. Does the "FTPS" parameter with acceleration 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 1 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.
CAUTION: 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. Monitor and record the Freeze Frame Data for the Diagnostic Trouble Code (DTC) which has been diagnosed.
2. Using a Scantool, Clear the DTCs
3. Operate the vehicle within conditions noted in the freeze frame data or enable conditions
4. Monitor that all readiness test have been verified as "Complete"
5. Are any DTCs present?
YES - Go to the applicable troubleshooting procedure.
NO - System is performing to specification at this time.