John Deere 2850.03 – CRU: Excessive Voltage Detected in Radio Antenna Circuit

This code is generated when the radio antenna circuit is either open or shorted to a 12-volt source, resulting in a voltage level that is too high for standard operations. If left unresolved, this excessive voltage can potentially damage the radio unit.

• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 5E
• 5M
• 6M
• 6R
• 7R
• 8R
• 8RT
• 9R
• 9RX
• 9RT
• 30 series
• 40 series
• 50 series
• 60 series
• 7000 series
• 8000 series
• 9000 series
• 4730
• 4830
• 4940
• 444J
• 544J
• 624J
• 744J
• 824J

1. 1

   Visual Inspection: Examine the antenna wiring thoroughly for any signs of breaks, disconnections, chafing, or wear that could lead to a short to a 12-volt source or an open circuit.

2. 2

   Connector Check: Inspect all radio and antenna connectors to ensure they are tight, properly seated, and completely free of moisture or corrosion.

3. 3

   Continuity & Voltage Test: Use a digital multimeter to perform a continuity test on the antenna circuit. Check the circuit for an unwanted short to a 12V power source. This will help isolate whether the fault is in the wiring harness, the antenna base, or the radio itself.

1. 1

   Disconnect Power

   Disconnect the machine's battery ground to prevent any further electrical damage during testing and repair.

2. 2

   Isolate the Fault

   Based on the multimeter test, locate the exact point of the short or open circuit.

3. 3

   Repair/Replace Wiring

   If the wiring harness is damaged or shorted to a 12V source, repair the affected section of the wire or replace the harness segment.

4. 4

   Replace Antenna Components

   If the wiring tests fine but the antenna base has internally shorted, replace the antenna base and/or mast.

5. 5

   Verify Functionality

   Reconnect the battery. Turn on the machine and test the radio to ensure it is receiving signals correctly without audio clipping or static.

6. 6

   Clear Codes

   Access the diagnostic menu on the CommandCenter/display, clear the CRU 002850.03 error code, and reset the control software. Conduct a full system check to ensure the code does not return.