Deutz-Fahr 158 – ECU: Injector Power Stage B Fault

The engine control unit (ECU) has detected an internal malfunction within the Injector Power Stage B circuit, which is responsible for providing electrical power to operate the fuel injectors. This is a non-self-curing internal ECU error (SPN 523355, FMI 12) that will remain active until the underlying issue is resolved and the ECU is reset.

• Tractors with TCD 2012 engine
• Tractors with TCD 2013 engine

1. 1

   Visually inspect the wiring harness connected to the EMR3 ECU for chafing, corrosion on connector pins, loose connections, or broken wires.

2. 2

   Verify the ECU has a stable, correct voltage supply and a solid ground connection, as poor power or ground can trigger internal errors.

3. 3

   Perform a full ECU reset by switching the ignition off, waiting at least 10 seconds for the main relay to switch off, and switching it back on to determine if the fault is intermittent.

4. 4

   Connect Deutz SerDia diagnostic software to read the fault code directly and view live engine data.

1. 1

   Obtain replacement ECU

   Ensure the replacement EMR3 ECU part number exactly matches the original based on the engine serial number.

2. 2

   Disconnect power

   Disconnect the vehicle's battery to prevent electrical damage during the replacement process.

3. 3

   Remove faulty ECU

   Carefully disconnect all electrical connectors from the EMR3 ECU and unbolt it from its mounting bracket.

4. 4

   Install new ECU

   Mount the replacement ECU, securely fasten all electrical connectors, and reconnect the vehicle's battery.

5. 5

   Program the ECU

   Use the Deutz SerDia diagnostic tool to load the correct engine dataset into the new ECU. This is required to match the ECU to the engine's parameters and vehicle configuration. Without this programming, the engine may not start or run correctly.