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P1451

Read the instructions below then start the fault diagnostic procedure.

Symptom: CHECK ENGINE.

P1451


EVAP Tank Pressure Sensor.Performance Problem.


Fault symptoms


• CHECK ENGINE.


On-Board Diagnostics

Type of diagnosis:


- Once per driving cycle. Interrupted when fault criteria fulfilled or OK reported. Restarts next driving cycle.


Enable criteria


- General condition for this diagnostic trouble code: Atmospheric pressure must exceed 72 kPa as well as coolant and intake air temperature must exceed -7°C.

- Accepted transition diagnosis of oxygen sensor 1. Purge active. Idling. Max. one change in status of brake light switch. Purge adaptation higher than -7%. Car stationary for 8 s.

The diagnosis will start once the above conditions have been fulfilled. If the diagnosis is interrupted then the speed must exceed 0 on one occasion before it is allowed to restart.


Fault criteria


- Tank pressure pulsating at a frequency higher than 5.6 Hz with an amplitude exceeding 0.020 kPa.


Generating diagnostic trouble codes


- Diagnostic Trouble Codes are generated if the fault criteria are fulfilled and the dependants are OK.


Dependents


- P0444, P0445, P0501, P0502, P0506, P0507, P1444, P1445, P1576 and P1577.


System reaction to a fault


- Integrity diagnosis of purge system blocked.


OK report


- Diagnoses for P1451, P1452 and P1453 performed once and fault criteria not fulfilled. Fault criteria for P0452 or P0453 not fulfilled.


Fault handling: (For more information, see .)


- Type III.


Diagnostic help

Fault diagnosis concerns an electrical fault in connecting leads or in the sensor.

Functions in the diagnostic tool related to the fault:


• Diagnostic status for the diagnosis.

• Tank pressure value, unit kPa. The value should be approx. 0 kPa with the filler cap removed. When the car is stationary, the value should be stable.


For more information, see .

Checking the wiring

Jiggle the wiring harness at several points and in different directions to detect intermittent breaks and short circuits. Observe the multimeter, diagnostic tool or test lamp during the check.