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P0129

DTC P0129 - 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

GENERAL DRIVING CYCLE
Perform the diagnosis once turning the ignition switch to ON.

DIAGNOSTIC METHOD




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




- Normality Judgment
Judge OK and clear the NG when the continuous time of completing the malfunction criteria becomes more than 0.262 seconds.

DTC CLEAR CONDITION
- 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)