John Deere 004360.07 – ECU: SCR Inlet Temperature Invalid

The SCR inlet temperature reading is outside of its expected range (too high, too low, or erratic). This indicates that the sensor is not functioning correctly or is providing invalid data, which prevents the system from accurately managing Diesel Exhaust Fluid (DEF) injection and other after-treatment processes. This condition can lead to reduced engine performance, increased emissions, and the engine entering a derated state.

• 8R Series
• 8245R
• 8270R
• 8295R
• 8320RT
• 8345RT
• 8370RT
• 8400
• 9R Series
• 9370R
• 9420R
• 9470R
• 9470RT
• 9470RX
• 9520R
• 9520RT
• 9520RX
• 6R Series
• 6M Series
• W235R
• R4030
• R4038
• R4045
• 250G
• 300G
• 350G
• 380G
• 470G
• 670G
• 770G
• 870G
• 624K
• 644K
• 724K
• 750K
• 824K
• 844K
• 850K
• 1050K
• G Series
• K Series
• L Series
• 5075GN
• 5090G
• 5105GF
• 5G Series

1. 1

   Inspect the wiring harness and connectors for the SCR inlet temperature sensor for signs of damage, such as chafing, melting, corrosion, or loose connections

2. 2

   Check the exhaust system for any leaks between the Diesel Particulate Filter (DPF) and the SCR inlet, which can cause inaccurate temperature readings

3. 3

   Verify the sensor is correctly installed and has good thermal contact with the exhaust system

4. 4

   Use a diagnostic scanner to monitor live data from the SCR inlet temperature sensor for erratic or implausible readings, and use a multimeter to test the sensor's circuit for continuity and correct voltage levels

5. 5

   After any inspection or repair, clear the fault codes and operate the machine to see if the code returns

1. 1

   Prepare machine

   Park the machine on level ground, engage the parking brake, lower all equipment, stop the engine, and remove the key. Disconnect the battery ground strap before working on the electrical system.

2. 2

   Locate sensor

   Locate the SCR inlet temperature sensor or module in the exhaust system, positioned before the SCR catalyst.

3. 3

   Remove faulty component

   Disconnect the electrical connector from the sensor or module. Carefully remove the sensor from the exhaust housing. On some models, like the W235R windrower, the entire temperature module with its multiple sensors is replaced as a single unit.

4. 4

   Install new component

   Install the new SCR inlet temperature sensor or module and tighten to manufacturer specifications. If reusing a sensor, apply anti-seize compound to the threads.

5. 5

   Reconnect system

   Reconnect the electrical connector and the battery ground strap.

6. 6

   Clear codes and test

   Start the machine, use a diagnostic tool to clear the fault code, and operate the machine to ensure the fault does not return.