| Mazda P1412 | EGR valve frozen |
|---|---|
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DETECTION CONDITION
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• The PCM monitors the input voltage from the EGR valve position sensor signal. If the voltages at PCM terminal 129 deviates from the threshold, the PCM determines that the there is a EGR valve malfunction.
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POSSIBLE CAUSE
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• EGR valve servo motor malfunction
• Contaminate on EGR valve
• EGR valve position sensor malfunction
• Vent or damage in the wiring harness between EGR valve servo motor and PCM
• PCM malfunction
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Diagnostic procedure
| STEP | INSPECTION | ACTION | |
|---|---|---|---|
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1
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VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
• Has the FREEZE FRAME DATA been recorded?
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Yes
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Go to the next step.
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No
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Record the FREEZE FRAME DATA on the repair order, then go to the next step.
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2
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VERIFY REPAIR INFORMATION AVAILABILITY
• Verify related service repair information availability.
• Is any related repair information available?
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Yes
|
Perform repair or diagnosis according to the available repair information.
If the vehicle is not repaired, go to the next step.
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No
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Go to the next step.
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3
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IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA
• Is DTC P1412 on FREEZE FRAME DATA?.
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Yes
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Go to the next step.
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No
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Go to the troubleshooting procedures for DTC in FREEZE FRAME DATA.
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4
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INSPECT THE WIRING HARNESS FOR VENT AND/OR DAMAGE
• Inspect for vent and/or damage in the wiring harness between EGR valve and PCM.
• Is there any malfunction?
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Yes
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Repair or replace the malfunctioning part, then go to Step 8.
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No
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Go to the next step.
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5
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INSPECT OPERATION OF EGR VALVE
• Remove the EGR valve with connector connected.
• Connect the M-MDS to DLC-2.
• Turn the engine switch to the ON position (Engine off).
• Access PID EgrDc
• Visually inspect the EGR valve operation using the PID EgrDc of simulation function.
• Does the EGR valve move smoothly?
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Yes
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Go to Step 7.
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No
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Clean the EGR valve, then go to the next step.
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6
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INSPECT EGR VALVE SERVO MOTOR
• Inspect the EGR valve servo motor.
• Is the EGR valve servo motor normal?.
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Yes
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Go to the next step.
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No
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Replace the EGR valve, then go to Step 8.
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7
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INSPECT EGR VALVE POSITION SENSOR
• Inspect the EGR valve position sensor.
• Is the EGR valve position sensor normal?.
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Yes
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Go to the next step.
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No
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Replace the EGR valve, then go to the next step.
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8
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VERIFY THAT DTC P1412 TROUBLESHOOTING IS COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear DTC from PCM memory using M-MDS.
• Start the engine and warm-up to normal operating temperature.
• Run the vehicle under the FREEZE FRAME DATA stored condition.
• Is the PENDING CODE for this DTC present?
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Yes
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Replace PCM, then go to the next step.
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No
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Go to the next step.
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9
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VERIFY AFTER REPAIR PROCEDURE
• Perform the after repair procedure.
• Are any DTCs present?
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Yes
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Go to the applicable DTC inspection.
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No
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DTC troubleshooting completed.
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