CLAAS Id76A5h / 76A5h (716) – REH (A58) / Auto 5: 12V supply of the REH module or 10V regulated voltage non valid.

The lifting module is either not receiving a valid 12V power supply from the tractor's electrical system, or the module's internal 10V regulated reference voltage (used to power external sensors like draft pins and position sensors) has failed or shorted. The rear lifting (hitch) function is locked and rendered inactive.

• CLAAS Arion 410
• CLAAS Arion 430
• CLAAS Arion 510
• CLAAS Arion 530
• CLAAS Arion 550
• CLAAS Arion 610
• CLAAS Arion 620
• CLAAS Arion 630
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• CLAAS Axion 810
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• CLAAS Axion 950
• CLAAS Axos Series

1. 1

   Verify the 12V power supply to the REH (A58) module. Check the tractor's battery voltage, the main cab relays, and the specific fuses supplying the rear lifting module.

2. 2

   Inspect the wiring harness and the multi-pin connectors at the module (typically located behind the operator's seat on the control board) for corrosion, water ingress, or burnt pins.

3. 3

   Using a multimeter, check the 10V regulated output from the module to the hitch sensors (e.g., draft load sensors, position sensors). Disconnect the sensors one by one to see if the 10V reference returns, indicating a shorted sensor.

4. 4

   Verify that the ground pins on the Auto 5 module have clean, low-resistance continuity to the chassis.

1. 1

   Isolate power

   Turn off the tractor ignition and disconnect the battery.

2. 2

   Locate the module

   Access the REH (A58) / Auto 5 module, which is generally mounted behind the seat on the main electronic control board.

3. 3

   Clean and repair harness

   Disconnect the harness. If corrosion is found, clean the pins thoroughly with electrical contact cleaner. Repair any damaged wires.

4. 4

   Test and repair external shorts

   If the wiring is clean, test the external sensor harness for shorts. If a sensor is shorting the 10V reference, replace the faulty sensor or repair the chafed wire.

5. 5

   Replace or repair module

   If the 12V supply and grounds are good, and no external shorts are dragging down the 10V reference, the Auto 5 module has suffered an internal failure (often due to moisture). The module must be replaced or sent to an agricultural electronics specialist for remanufacturing.

6. 6

   Calibrate the system

   After installing a new or repaired Auto 5 module, use the CLAAS Diagnostic System (CDS) to program the module to the tractor and perform a rear lifting calibration procedure so it can relearn the hitch parameters.