Case IH 17652 (F-518397-04) - ECU – Engine Control Unit (ECU) / Bosch MD1CE101: ECU 12/24 volt actuator supply 5 is shorted to battery voltage.

The Engine Control Module has detected that the voltage on actuator supply circuit 5 is abnormally high, meaning the circuit is shorted directly to the battery voltage. The specific pins on the ECU connector for this supply circuit are 5.07 and 6.41.

• VESTRUM CVX
• Magnum CVT/CVX (265-400)
• Maxxum CVX (115-180)
• Optum CVX (250-340)
• Puma CVX / Puma X (140-260)
• Steiger (385-555)
• Quadtrac (475-715)
• Axial Flow 5150
• Axial Flow 6150
• Axial Flow 7150
• Axial Flow 7160
• Axial Flow 7250
• Axial Flow 8250
• Axial Flow 8260
• Axial Flow 9250
• Patriot 3250
• Patriot 4450
• Farmlift 737
• Farmlift 742
• Case IH Graders (836C)
• Wheel Loaders (621G, 721G, 821G, 1021G)

1. 1

   Pinpoint Testing: Locate the Bosch MD1CE101 ECU and identify pins 5.07 and 6.41 on the harness connector.

2. 2

   Harness Inspection: Visually inspect the wiring harness leading from these pins to the engine actuators for chafing, melted insulation, or exposed wires touching a 12V/24V power source.

3. 3

   Multimeter Check: With the battery disconnected, test for continuity between the actuator supply 5 circuit wires and the battery positive terminal.

4. 4

   Actuator Isolation: Disconnect the actuators powered by supply 5 one by one. If the short to battery voltage disappears when a specific actuator is unplugged, that actuator has an internal short.

5. 5

   ECU Pin Inspection: Check the ECU header pins for corrosion, water ingress, or bent pins that could be bridging the supply circuit to a power pin.

1. 1

   Disconnect Power

   Turn off the machine and disconnect the negative battery cable to prevent electrical damage.

2. 2

   Isolate the Short

   Unplug the main harness from the Bosch MD1CE101 ECU.

3. 3

   Test the Harness

   Using a digital multimeter, probe pins 5.07 and 6.41 on the harness side. If a short to battery voltage is present, trace the wiring harness to locate the fault.

4. 4

   Repair Wiring / Replace Actuator

   If the wiring harness is rubbed through and touching a live wire, repair the damaged section using OEM-approved heat-shrink connectors, or replace the harness section. If an actuator is internally shorted, replace the faulty actuator.

5. 5

   Test the ECU

   If the harness and all actuators test perfectly fine, the short may be internal to the Bosch MD1CE101 ECU itself. In this case, the ECU must be replaced and reprogrammed by a dealer or tuning specialist.

6. 6

   Clear Codes

   Reconnect the battery, turn the key to the ON position, and use a diagnostic tool to clear the inactive 17652 fault code. Run the engine to verify the code does not return.