Description:

The error code ETC 523979.05 is triggered when the control unit measures too low an amperage at the signal input of the indicator light in the rear window heater switch (S139, lead 2021). This indicates an interruption in the circuit or, on tractors without the optional “heated rear window”, an incorrect entry at input address ETC036.

Reaction:

When this fault is detected, the control unit may disable or limit the operation of the rear window heater indicator light, potentially leading to incorrect or no indication of the heater’s status.

Recommendations:

Inspect Electrical Circuits:

• Check for Interruptions: Inspect the wiring and connectors for the rear window heater switch (S139) for signs of interruptions or open circuits. Look for broken wires, loose connections, or damaged insulation.
• Measure Current Flow: Use a multimeter to measure the current flow at the signal input of the indicator light to ensure it is within the specified range.

Check Configuration:

• Verify Input Address: On tractors without the optional “heated rear window”, ensure the input address ETC036 is correctly configured to prevent incorrect entries.

Test and Replace Components:

• Test Rear Window Heater Switch: Verify the operation of the rear window heater switch (S139). Replace the switch if it is found to be malfunctioning or not providing the correct signal.
• Inspect Control Unit: Ensure that the control unit is functioning correctly. Replace the control unit if it is found to be faulty.

Repair or Replace Wiring:

• Fix Interruptions: Repair or replace any interrupted or faulty wiring in the rear window heater switch circuit. Ensure all connections are secure and properly insulated.

Note:

Maintaining the integrity of the electrical connections and ensuring proper current flow is crucial for the reliable operation of the rear window heater indicator light. Regular inspection and timely repairs of the electrical system can help prevent issues related to low current and ensure proper system performance.