John Deere 000247.09 – CCU: CCU CAN BUS Message Missing

The system has detected that messages are missing on the Power Train CAN BUS, specifically from the Central Control Unit (CCU). This indicates a communication breakdown between the CCU and other control modules (such as the Engine Control Unit or Transmission Control Unit) that rely on its data. The issue can stem from a faulty CCU, damaged CAN bus wiring or connectors, or faulty terminating resistors, leading to warning lights or a complete loss of function in related systems.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M

1. 1

   Visually inspect the Power Train CAN bus wiring harness for chafing, cuts, pinched wires, or corrosion, especially around the CCU and main harness routes.

2. 2

   Check all related connectors for tightness, pin corrosion, or damage.

3. 3

   Confirm the battery is fully charged and terminals are clean and tight, as low voltage can cause CAN faults.

4. 4

   Check fuses related to the CCU and other control modules on the CAN network.

5. 5

   Perform a CAN Bus resistance check (key off, battery disconnected) between CAN High (yellow) and CAN Low (green). Expected: ~60 Ohms. 120 Ohms indicates an open circuit or missing resistor; significantly lower indicates a short.

6. 6

   Perform CAN Bus voltage tests (key on) relative to chassis ground. CAN High (yellow) should be 2.5-3.0V; CAN Low (green) should be 2.0-2.5V. Incorrect voltages can point to a short to power or ground in the wiring or a faulty control module.

1. 1

   Repair wiring and connectors

   If damage was found during visual inspection, repair or replace the affected sections of the wiring harness. Clean corroded connectors and ensure all connections are secure.

2. 2

   Replace terminating resistors

   If the resistance check indicated a problem, locate and test the two 120-Ohm terminating resistors individually. Replace any faulty resistors.

3. 3

   Isolate faulty module

   If wiring and resistors are good, disconnect modules one by one from the CAN bus and re-check resistance and voltages. If the bus returns to normal after disconnecting a module, that module is the source. The CCU is the primary suspect.

4. 4

   Replace Central Control Unit (CCU)

   If the CCU is determined to be faulty, replace it. The new module will require programming by a certified John Deere technician to communicate correctly.