Nissan Maxima Service and Repair Manual: P0451 evap control system pressure sensor
Description
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The EVAP control system pressure sensor detects pressure in the
purge line. The sensor output voltage to the ECM increases as pressure
increases
DTC Logic
DTC DETECTION LOGIC
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DTC CONFIRMATION PROCEDURE
NOTE:
Never remove fuel filler cap during DTC confirmation procedure.
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform
the following procedure
before conducting the next test.
- Turn ignition switch OFF and wait at least 10 seconds.
- Turn ignition switch ON.
- Turn ignition switch OFF and wait at least 10 seconds.
2.PERFORM DTC CONFIRMATION PROCEDURE-1
With CONSULT
- Start engine and let it idle for least 40 seconds.
NOTE:
Do not depress accelerator pedal even slightly.
- Check 1st trip DTC
3.PERFORM DTC CONFIRMATION PROCEDURE-2
With CONSULT
- Select "EVAP DIAG READY" in "DATA MONITOR" mode of "ENGINE".
- Let it idle until "OFF" of "EVAP DIAG READY" changes to "ON".
NOTE:
It will take at most 2 hours until "OFF" of "EVAP DIAG READY" changes to
"ON".
- Turn ignition switch OFF and wait at least 90 minutes.
NOTE:
Never turn ignition switch ON during 90 minutes.
- Turn ignition switch ON.
- Select "EVAP LEAK DIAG" in "DATA MONITOR" mode of "ENGINE".
- Check that "EVAP LEAK DIAG" indication.
4.PERFORM DTC CONFIRMATION PROCEDURE-3
With CONSULT
Check 1st trip DTC.
5.PERFORM DTC CONFIRMATION PROCEDURE-4
With GST
- Start engine and let it idle for least 40 seconds.
NOTE:
Do not depress accelerator pedal even slightly.
- Check 1st trip DTC.
6.PERFORM DTC CONFIRMATION PROCEDURE-5
With GST
- Let it idle for at least 2 hours
- Turn ignition switch OFF and wait at least 90 minutes.
NOTE:
Never turn ignition switch ON during 90 minutes.
- Turn ignition switch ON.
- Check 1st trip DTC.
Diagnosis Procedure
1.CHECK GROUND CONNECTION
- Turn ignition switch OFF.
- Check ground connection E9.
2.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR CONNECTOR FOR WATER
- Disconnect EVAP control system pressure sensor harness connector.
- Check that water is not inside connectors.
3.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR POWER SUPPLY CIRCUIT
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- Turn ignition switch ON.
- Check the voltage between EVAP control system pressure sensor
harness connector and ground.
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4.CHECK SENSOR POWER SUPPLY CIRCUIT
Check harness for short to power and short to ground, between the following
terminals.
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5.CHECK COMPONENTS
Check the following.
- Crankshaft position sensor (POS) (Refer to EC-299, "Component
Inspection".)
- Refrigerant pressure sensor
6.CHECK APP SENSOR
7.REPLACE ACCELERATOR PEDAL ASSEMBLY
- Replace accelerator pedal assembly.
8.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
9.CHECK INTERMITTENT INCIDENT
Component Inspection
1.CHECK EVAP CONTROL SYSTEM PRESSURE SENSOR
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- Turn ignition switch OFF.
- Remove EVAP control system pressure sensor with its harness
connector.
Always replace O-ring with a new one.
- Install a vacuum pump to EVAP control system pressure sensor.
- Turn ignition switch ON and check output voltage between ECM
terminals under the following conditions.
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CAUTION:
- Always calibrate the vacuum pump gauge when using it.
- Never apply below -93.3 kPa (-0.952 kg/cm2, -13.53 psi) or
pressure over 101.3 kPa (1.033 kg/cm2,
14.69 psi).
Description
The EVAP canister vent control valve is located on the EVAP canister
and is used to seal the canister vent.
This solenoid valve responds to signals from the ECM. When the
ECM s ...
Description
The EVAP control system pressure sensor detects pressure in the
purge line. The sensor output voltage to the ECM increases as pressure
increases.
DTC Logic
DTC DETECTION LOGIC
...
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Periodic maintenance
SQUEAK AND RATTLE TROUBLE DIAGNOSES
Work Flow
CUSTOMER INTERVIEW
Interview the customer if possible, to determine the conditions that exist
when the noise occurs. Use the Diagnostic Worksheet during the interview to
document the facts and conditions when the noise occurs and any customer's ...
TCM branch line circuit
Diagnosis Procedure
1.CHECK CONNECTOR
Turn the ignition switch OFF.
Disconnect the battery cable from the negative terminal.
Check the following terminals and connectors for damage, bend and
loose connection (unit side and connector
side).
TCM
Harness connector F1
Harness con ...