3000 - 3999: 3087

3087-CATALYTIC CONVERTER TEMPERATURE SENSOR OR TEMPERATURE SENSOR UPSTREAM OF DIESEL PARTICULATE FILTER FAULTY

- When Monitored:
With the engine running.

- Set Condition:
The Engine Control Module (ECM) detects an implausible signal from the Catalytic Converter Temperature Sensor.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview

1. DTC IS ACTIVE
1. Turn the ignition on, engine not running.
2. With the scan tool, clear DTCs in the Engine Control Module (ECM).
3. Start the engine and monitor the scan tool for at least two minutes.
4. Perform several engine run cycles, turning the ignition off for at least 20 seconds between each engine run cycle.
5. With the scan tool, select View DTCs.
Is the status Active for this DTC?

Yes

- Go To 2

No

- Perform the INTERMITTENT DTC diagnostic procedure. Component Tests and General Diagnostics

2. CATALYTIC CONVERTER TEMPERATURE SENSOR SIGNAL CIRCUIT OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the Catalytic Converter Temperature Sensor harness connector.
3. Disconnect the Engine Control Module harness connector.
4. Measure the resistance of the Catalytic Converter Temperature Sensor Signal circuit between the Catalytic Converter Temperature Sensor harness connector and the Engine Control Module harness connector.
Is the resistance below 5.0 Ohms?

Yes

- Go To 3

No

- Repair the open or high resistance in the Catalytic Converter Temperature Sensor Signal circuit.
- Perform the ECM Verification Test. Verification Tests

3. CATALYTIC CONVERTER TEMPERATURE SENSOR GROUND CIRCUIT OPEN/HIGH RESISTANCE
1. Measure the resistance ofthe Catalytic Converter Temperature Sensor Ground circuit between the Catalytic Converter Temperature Sensor harness connector and the Engine Control Module harness connector.
Is the resistance below 5.0 Ohms?

Yes

- Go To 4

No

- Repair the open or high resistance in the Catalytic Converter Temperature Sensor Ground circuit.
- Perform the ECM Verification Test. Verification Tests

4. CATALYTIC CONVERTER FILTER TEMPERATURE SENSOR





1. Using the table as a guide, measure the resistance of the Catalytic Converter Temperature Sensor.
Is the resitance reading within specifications?

Yes

- Replace the Engine Control Module.
- Perform the ECM Verification Test. Verification Tests

No

- Replace the Catalytic Converter Temperature Sensor.
- Perform the ECM Verification Test. Verification Tests