John Deere 2025.09 – ECU, ICU, DTI, PDU, RLC: Incorrect CAN Bus Message, Information from ATC/ETC Control Software

Data transfer problem between the Automatic Temperature Control Unit (ATC) or Engine Temperature Controller (ETC) and the reporting module. The reception of CAN messages transmitted by the ATC/ETC control software is intermittent or non-existent, typically caused by an open circuit, short circuit, faulty CAN Bus terminating resistors, or a blown fuse cutting power to the ATC module.

• 5085E
• 5090E
• 5090EL
• 5100E
• 5085M
• 5100M
• 5100MH
• 5100ML
• 5115ML
• 5090M
• 5115M
• 6120
• 6220
• 6320
• 6420
• 6150R
• 6230
• 6330
• 6430
• 6530
• 7130
• 7230
• 7330
• 7430
• 7530
• 7630
• 7720
• 7730
• 7810
• 7820
• 7830
• 7920
• 7930
• 8120
• 8220
• 8320
• 8420
• 8520
• 9230
• 9330
• 9430
• 9530
• 9630
• E360
• E360LC

1. 1

   Restart the vehicle to see if resetting the communication messages clears the code

2. 2

   Check fuses (F42, F30, or F6 depending on model) that power the ATC module

3. 3

   Inspect the CAN Bus network wiring harness between the ATC/ETC and the ECU for physical damage, loose connections, or corrosion

4. 4

   Measure CAN Bus signal integrity by testing the terminating resistors (should read approximately 60 ohms across CAN High and CAN Low with the battery disconnected)

1. 1

   Power Down

   Turn off the engine and locate the cab fuse panel.

2. 2

   Fuse Replacement

   Inspect the ATC communication fuses (F42, F30, or F6). If blown, replace the fuse and restart the vehicle to verify if the active Diagnostic Trouble Code reappears.

3. 3

   Harness Inspection

   If the code returns, access the CAN bus wiring harness connecting the Automatic Temperature Control (ATC) unit to the main ECU/ICU.

4. 4

   Clean Connections

   Inspect all connectors for looseness, damage, or corrosion. Clean the pins and securely reseat the connectors.

5. 5

   Test Terminating Resistors

   Locate the CAN Bus terminating resistors on the network. If a terminating resistor is found to be faulty (reading open or shorted instead of the standard resistance), replace it to restore proper network function.

6. 6

   Module Replacement

   If the wiring, fuses, and resistors are all intact, the ATC module itself has likely failed and is no longer broadcasting messages. Replace the ATC module.

7. 7

   Reset and Re-test

   Clear the stored error codes and conduct a thorough test of the climate control and engine systems to ensure all functionalities are active and error-free.