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DTC P1497 EGR SOLENOID VALVE SIGNAL #3 CIRCUIT MALFUNCTION (HIGH INPUT)

DTC P1497 EGR SOLENOID VALVE SIGNAL #3 CIRCUIT MALFUNCTION (HIGH INPUT)

OUTLINE OF DIAGNOSIS


• Detect the open/short circuit of EGR.

• Judge NG when ECM output level is different from actual terminal level.


COMPONENT DESCRIPTION


(1)

Engine Control Module (ECM)

(3)

Detecting circuit

(5)

Battery voltage

(2)

CPU

(4)

Switching circuit

(6)

Main relay



ENABLE CONDITION

Secondary Parameters Enable Conditions
Battery voltage

> 10.9 V



GENERAL DRIVING CYCLE

Always perform the diagnosis continuously.

DIAGNOSTIC METHOD

Abnormality Judgment

Judge NG when the continuous time until completing the malfunction criteria below becomes more than time needed for diagnosis.

Malfunction Criteria Threshold Value
Terminal voltage level when ECM outputs ON signal

High level



Time Needed for Diagnosis: 2.5 seconds

Malfunction Indicator Light Illumination: Illuminates as soon as malfunction occurs.

Normality Judgment

Judge OK and clear the NG when the malfunction criteria below are not completed.

Judgment Value

Malfunction Criteria Threshold Value
Terminal voltage level when ECM outputs OFF signal

Low level



DTC CLEAR CONDITION


• When the OK idling cycle is 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


• Front oxygen (A/F) sensor main learning compensation: Not allowed to calculate

• Knock sensor learning compensation: Not allowed to calculate

• EGR control: Not allowed to operate


ECM OPERATION AT DTC SETTING

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