Test Procedure
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- DS1 CHECK FOR DTCS
Are DTCs P041B, P041C or P041D present?
Yes No GO to DS2 For symptoms without DTCs, GO to DS2
For all others, RETURN to Symptom Charts for further direction. - DS2 CHECK THE EGRT12 SENSOR
- Inspect the EGRT12 sensor circuits at the sensor and the PCM.
Is a concern present?
Yes No REPAIR as necessary.
Clear the PCM DTCs. REPEAT the self-test.GO to DS3 - DS3 CHECK FOR AN OPEN
- Ignition OFF.
- EGRT12 Sensor connector disconnected.
- PCM connector disconnected.
- Measure the resistance between:
(+) EGRT12 Sensor Connector, Harness Side (-) PCM Connector, Harness Side EGRT12 - Pin 1 EGRT12 SIGRTN - Pin 2 SIGRTN
Are the resistances less than 5 ohms?
Yes No GO to DS4 REPAIR the open circuit. Clear the PCM DTCs.
REPEAT the self-test. - DS4 CHECK FOR A SHORT TO GROUND
Is the resistance greater than 10K ohms?
Yes No GO to DS5 REPAIR the short circuit. Clear the PCM DTCs.
REPEAT the self-test. - DS5 CHECK FOR A SHORT TO VOLTAGE
- Ignition ON, engine OFF.
- Measure the voltage between:
(+) EGRT12 Sensor Connector, Harness Side (-) EGRT12 - Pin 1 Ground
Is any voltage present?
Yes No REPAIR the short circuit. Clear the PCM DTCs.
REPEAT the self-test.GO to DS6 - DS6 CHECK THE EGRT SENSOR OPERATION
- Ignition OFF.
- EGRT12 Sensor connector connected.
- PCM connector connected.
- Ignition ON, engine OFF.
- Access the PCM and monitor the EGRT12 (TEMP) PID.
- Record the PID value.
- Drive the vehicle while monitoring the PID.
- Engine at normal operating temperature.
- Record the PID value.
Does the PID value increase?
Yes No For symptoms without DTCs, RETURN to Symptom Charts for further direction.
For all others, GO to Pinpoint Test Z.INSTALL a new EGRT sensor. REFER to the appropriate Engine Emission Control article.
Clear the PCM DTCs. REPEAT the self-test.