Case IH 19596 – DCU (Dosing Control Unit) / ATC (Automatic Temperature Control) / Tractor Systems Modules: CAN receive frame EEC1 (Driver demand, eng speed, eng torque) | SAE J1939 Check for CAN receive signal : (Engine speed not in range) | P0600 Serial Communication Link

This code indicates a serial communication error (P0600) on the SAE J1939 CAN bus network. Specifically, the control module is receiving the EEC1 (Electronic Engine Controller 1) data frame, but the engine speed data contained within that message is registering as 'not in range' (invalid or erratic).

• Tier 4a
• Magnum Series 235
• Magnum Series 260
• Magnum Series 290
• Magnum Series 315
• Magnum Series 340 (Series 4)
• Steiger & Rowtrac Series 350
• Steiger & Rowtrac Series 400
• Steiger & Rowtrac Series 450
• Steiger & Rowtrac Series 500
• Steiger & Rowtrac Series 550
• Steiger & Rowtrac Series 600
• Puma Series

1. 1

   Check for related CAN bus codes (like 19597 for CAN timeout or 19598 for too many CAN messages) or Engine Speed Sensor codes (e.g., ENG 115).

2. 2

   Use the Electronic Service Tool (EST) to monitor the live engine speed signal to determine if the engine ECU is broadcasting an erratic speed signal, or if the DCU is failing to interpret it.

3. 3

   Test the SAE J1939 CAN bus lines between the Engine ECU and the DCU for continuity, shorts to ground, or shorts to power.

4. 4

   Measure the resistance across the CAN bus network to ensure the terminating resistors are intact (typically 60 ohms when the battery is disconnected).

1. 1

   Disconnect Power

   Turn off the machine and disconnect the battery to prevent electrical spikes during harness inspection.

2. 2

   Inspect Connectors

   Locate the J1939 CAN bus connectors at the Engine ECU and the DCU. Disconnect them and inspect for pushed pins, corrosion, moisture, or spread terminals. Clean with contact cleaner and apply dielectric grease if necessary.

3. 3

   Repair the Harness

   If the diagnostic checks revealed an open or shorted CAN wire, repair the damaged section of the wiring harness or replace the affected CAN pigtail.

4. 4

   Address the Speed Sensor

   If the EST showed the engine speed was genuinely dropping out or reading out of range at the source, replace the Engine Speed Sensor (or Cam/Crankshaft sensor depending on the engine displacement).

5. 5

   Clear and Retest

   Reconnect the battery, clear the fault code 19596 using the diagnostic tool, and run the engine to verify that the EEC1 CAN frame is being received correctly and the code does not return.