Massey Ferguson E4792.02 – Engine Control Unit (ECU): Issue With The DOC Temperature (ECU)

The Engine Control Unit is receiving erratic, incorrect, or cross-connected data from the Diesel Oxidation Catalyst (DOC) upstream temperature sensor. This sensor monitors the exhaust temperature entering the DOC to ensure proper NOx conversion and to provide overheat protection for the aftertreatment system.

• 7616
• 5612
• 7622
• Interim Tier 4 (2012-2015)
• 7614
• 5611
• 7615
• 5610
• 5613
• 7620
• 5609
• 7618
• 5608
• 7619
• 7626
• 7624
• MF 4707
• MF 4708
• MF 4709
• MF 4710
• MF 5608
• MF 5609
• MF 5610
• MF 5611
• MF 5612
• MF 5613
• MF 5710 SL
• MF 5711 SL
• MF 5712 SL
• MF 5713 SL
• MF 7614
• MF 7615
• MF 7616
• MF 7618
• MF 7619
• MF 7620
• MF 7622
• MF 7624
• MF 7626
• MF 7714
• MF 7715
• MF 7716
• MF 7716S
• MF 7718
• MF 7718S
• MF 7719
• MF 7720
• MF 7720S
• MF 7722
• MF 7722S
• MF 7724
• MF 7724S
• MF 7726
• MF 7726S

1. 1

   Check the wiring harness leading to the upstream DOC temperature sensor for chafing, open circuits, or short circuits.

2. 2

   Ensure the DOC temperature sensor harness hasn't been accidentally swapped with the SCR temperature sensor or DPF temperature sensor connectors during previous maintenance.

3. 3

   Verify the closed-tip sensor receives a 5-volt supply on Pin 1, with Pin 2 acting as the common ground to the ECU using a multimeter.

4. 4

   Inspect the exhaust pipe and sensor housing upstream of the DOC for exhaust leaks, which can skew temperature readings.

1. 1

   Power Down

   Turn off the tractor and disconnect the battery to prevent electrical shorts and ensure the exhaust system has completely cooled down.

2. 2

   Locate the Sensor

   Locate the DOC temperature sensor on the exhaust aftertreatment system. It will be threaded into the exhaust piping directly upstream of the Diesel Oxidation Catalyst canister.

3. 3

   Disconnect

   Unplug the electrical connector from the sensor harness.

4. 4

   Removal

   Using an appropriately sized wrench or sensor socket, carefully unthread the faulty temperature sensor from the exhaust housing.

5. 5

   Installation

   Apply a small amount of anti-seize compound to the threads of the new sensor (if not pre-applied) and thread it into the housing. Tighten to the OEM specified torque.

6. 6

   Reconnect

   Plug the electrical connector back into the engine harness.

7. 7

   Clear Codes

   Reconnect the battery, turn the key to the ON position, and use a diagnostic tool (like the AGCO EST/WinEEM3s) to clear the E4792.02 / SPN 4792 fault code. Run the engine to verify the code does not return.