John Deere 1865.09 – CCU, SSU, or CLC: CAN BUS Message Fault (ELX Message Missing)

A communication failure on the CAN Bus where the reporting control unit has lost communication with the OIC or the ELX power center, meaning expected data packets are not being received. This is most commonly caused by a voltage drop, a blown ELX fuse, a failing ELX relay, or a physical wiring issue on the CAN Bus.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6090MC
• 6100MC
• 6110MC
• 6090RC
• 6100RC
• 6110RC
• 7810
• 7630
• 7730
• 7830
• 7930
• 8225R
• 8245R
• 8270R
• 8295R
• 8320R
• 8335R
• 8345R
• 8370R
• 8400R
• 8230T
• 8330T
• 8430T
• 9230
• 9330
• 9430
• 9530
• 9630
• 9470RT
• 9520RT
• 9570RT

1. 1

   Check battery health and alternator voltage (a drop in ELX voltage below 10V-11.2V can cause modules to drop offline)

2. 2

   Inspect the ELX fuse (10A or 15A) and ELX relay in the main fuse and relay load center

3. 3

   Inspect the CAN Bus wiring harness between the reporting module and the OIC/ELX power center for open circuits, short circuits, or corrosion

4. 4

   Verify CAN Bus terminating resistors are intact (should read 60 ohms across the bus when the machine is powered off)

1. 1

   Power Cycle & Verify

   Restart the tractor. If the code was triggered by a transient voltage drop during cranking, it may clear itself. If it returns, proceed to physical checks.

2. 2

   Relay Swap Test

   Locate the ELX relay in the cab load center. Swap the ELX relay with a known good relay of the same type (like the horn or worklight relay) to see if the fault clears. If it does, replace the relay.

3. 3

   Voltage Check

   Use a multimeter to check the voltage at the ELX fuse/relay block. Ensure it matches battery voltage (12V+). Check the battery terminals and ground connections (e.g., Lead 0310/terminal 31) for tightness and cleanliness.

4. 4

   Harness Routing Inspection

   Trace the CAN Bus wiring from the CCU/SSU to the cab load center. Look for chafing, especially near hot areas like the exhaust or moving linkages (a known issue on the 7000 series).

5. 5

   Connector Cleaning

   Disconnect the harness at the CCU/SSU and the OIC/Load Center. Spray with electrical contact cleaner, apply dielectric grease, and reconnect securely to eliminate pin fretting.

6. 6

   Software Update

   If wiring and power are verified good, the dealer may need to update the OIC and CCU/SSU control software, as outdated software glitches can cause message timeouts.