John Deere ICU002227.09 – ICU: SUP Message Missing

The Instrument Control Unit (ICU) has lost communication with the Setup Panel (SUP) controller, which is used to configure the functions of the selective control valves (SCVs). The '.09' suffix indicates that a message from the SUP is not being received by the ICU within the expected timeframe. This points to a CAN bus communication issue, a wiring problem, or an internal fault within the SUP controller itself.

• 7610
• 7710
• 7810
• 7715
• 7815
• 7720
• 7820
• 7920
• 7630
• 7730
• 7830
• 7930
• 8100
• 8120
• 8220
• 8320
• 8420
• 8520
• 8330
• 9100
• 9200
• 9300
• 9400
• 9120
• 9220
• 9320
• 9420
• 9520
• 9230
• 9330
• 9430
• 9530
• 9630

1. 1

   Restart the vehicle to see if the communication error is temporary and clears upon reboot

2. 2

   Check fuse F23, which is related to the power supply for the SUP and electro-hydraulic control valves

3. 3

   Inspect CAN bus wiring and connectors between the ICU and the SUP for damage, corrosion, or loose connections (red for 12V power, black for ground, yellow for CAN High, and green for CAN Low)

1. 1

   Verify power and ground

   Using a multimeter, confirm that the SUP controller is receiving the correct voltage and has a solid ground connection.

2. 2

   Check CAN bus integrity

   With the battery disconnected, measure the resistance between the CAN High (yellow wire) and CAN Low (green wire) pins at the diagnostic connector. A reading of approximately 60 ohms indicates intact terminating resistors. A reading of 120 ohms suggests an open circuit or a missing resistor.

3. 3

   Isolate the faulty controller

   If the CAN bus wiring appears intact, unplug controllers from the CAN network one at a time to see if communication is restored, which helps isolate a faulty module.

4. 4

   Address other SUP-related faults

   Check if the SUP controller has logged its own diagnostic codes (e.g., SUP 000629.12 for a control unit fault or SUP 00524013.03 for stuck keys) and resolve those first.

5. 5

   Replace the SUP controller

   If the SUP controller is determined to be faulty after verifying wiring and power, replace the unit.