P0453

PRESSURE SENSOR, FUEL TANK





Symptom Of Fault.
The CHECK ENGINE lamp (MIL) is on.

Conditions.
Ignition switch in ON position.
P0452 <0.1 V for more than 5 sec.
P0453 >4.96 V for more than 5 sec.

Diagnostic Help.
The pressure sensor reading can be obtained on an ISAT scan tool.

- Select"READ FUNCTIONS".
- Select"TANK PRESSURE"

The ISAT scan tool display should show about 0 kPa when the tiller cap is loosened.

Checking The Wiring
Intermittent faults may occur as a result of occasional short circuits and breaks in the wiring. Jiggle the leads and in-line connectors at several places and in different directions to reveal faults in the wiring harness. Observe the multimeter, ISAT scan tool or test lamp while carrying out this check.





Diagnostic Procedure.
1. Check the pressure sensor's ground connection and power supply

- Turn the ignition switch to the ON position and then back to the OFF position.

- Unplug the pressure sensor's 4-pin connector. The connector is located adjacent to the filler pipe under the car.

- Take voltage readings on the connector across:

^ pin 1 and a good grounding point about 5 V
^ pins 1 and 2 about 5 V.

Are pins 1 and 2 both OK?
YES: Continue with point 2.
NO: Repair or replace the relevant lead and then continue with point 3.





2. Check the engine control module's pressure sensor input

- Turn the ignition switch to the ON position and then back to the OFF position.
- Unplug the pressure sensor's 4-pinconnector.
- Connect an ISAT scan tool.
- Select "READ FUNCTIONS".
- Select "TANK PRESSURE" The reading obtained on the ISAT scan tool should be about -2.5 kPa.
- Connect a jumper lead between pins 1 and 3 of the pressure sensor's connector. The reading obtained on the ISAT scan tool should be about 2.5 kPa.

Are all readings OK?
YES: Change the pressure sensor and continue with point 3.
NO: Repair or replace the relevant lead and then continue with point 3.





3. Final check:

- Clear the diagnostic trouble code.
- Implementation of driving cycle: Drive the car at varying loads and engine rpm for 5 minutes.
- Evaluation of driving cycle: Check whether the diagnostic trouble code has recurred.

Has the diagnostic trouble code recurred?
YES: Proceed at "Before Replacing A Control Module". Component Tests and General Diagnostics
NO: The remedial measure taken was correct.