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DTC P2227 BAROMETRIC PRESSURE TOO LOW

DTC P2227 BAROMETRIC PRESSURE TOO LOW

OUTLINE OF DIAGNOSIS

Detect the malfunction of atmospheric pressure sensor output property. Judge NG when the atmospheric pressure sensor output is largely different from the intake manifold pressure at engine starting.

COMPONENT DESCRIPTION

Atmospheric pressure sensor is built in ECM.

ENABLE CONDITION

Secondary Parameters Enable Conditions
Engine speed

< 300 rpm

Vehicle speed

< 1 km/h (0.62 MPH)



GENERAL DRIVING CYCLE

Perform the diagnosis before engine starting with the ignition switch ON.

DIAGNOSTIC METHOD

Abnormality Judgment

Judge NG when the continuous time of completing the malfunction criteria below becomes more than 0.3 seconds.

Judgment Value

Malfunction Criteria Threshold Value
|Atmospheric − manifold absolute pressure|

≥ 26.7 kPa (200 mmHg, 7.88 inHg)

|Intake manifold pressure at engine starting − manifold absolute pressure|

< 1.33 kPa (10 mmHg, 2.95 inHg)



Time Needed for Diagnosis: 0.3 seconds

Malfunction Indicator Light Illumination: Detect when malfunction occurs in 2 continuous driving cycles.

Normality Judgment

Judge OK and clear the NG when the continuous time of completing the malfunction criteria below becomes more than 0.3 seconds.

Judgment Value

Malfunction Criteria Threshold Value
Atmospheric − manifold absolute pressure

< 26.7 kPa (200 mmHg, 7.88 inHg)



DTC CLEAR CONDITION n


• When the OK idling cycle was completed 40 times in a row

• When “Clear Memory” was performed


MALFUNCTION INDICATOR LIGHT CLEAR CONDITION


• When the OK driving cycle was completed 3 times in a row

• When “Clear Memory” was performed


FAIL SAFE

Atmospheric pressure sensor process: Fix the atmospheric pressure to 101 kPa (760 mmHg, 29.8 inHg).

ECM OPERATING AT DTC SETTING

Memorize the freeze frame data. (For test mode $02)