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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. It is interrupted once fault criteria have been fulfilled or OK has been reported. Restarts next driving cycle.


Enable criteria: (Conditions that must be fulfilled for diagnostics to be performed.)


- Global conditions for this diagnostic trouble code: When starting the engine, the atmospheric pressure must exceed 78 kPa and the temperature of the coolant and the intake air must exceed -7°C.

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

Diagnosis starts once the above conditions have been fulfilled. If diagnosis is interrupted, the speed will have to exceed 0 on one occasion before the diagnosis is allowed to restart.


Fault criteria: (When enable criteria have been fulfilled, diagnostics will check if the fault criteria have been fulfilled.)


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


Dependents: (Once fault criteria have been fulfilled, a number of other diagnostics must report OK before the diagnostic trouble code can finally be generated.)


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


System reaction to a fault: (Once the fault criteria have been fulfilled, certain measures will sometimes be taken.)


- Purge system integrity diagnosis blocked.


OK report: (This diagnosis may be included as a dependent to another diagnosis and must therefore report OK even if it is continuous. The OK report is also used in fault handling to count down the fault counter.)


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


Fault handling: (Refer to section “Fault diagnosis, general” for more information.)


- Type III.


Diagnostic help

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

Diagnostic tool functions related to this fault:


• Diagnostic status for the diagnosis.

• Pressure sensor reading, unit kPa. The value should be approx. 0 kPa with the filler cap removed and stable while the car is stationary.


Refer also to the description of readings under ”Fault diagnosis, general” for more information

Check the wiring

Jiggle the wiring harness at several points and in different directions to check if there are intermittent breaks and short-circuits in the leads. Observe the multimeter, test lamp or diagnostic instrument during the test.