Fendt 1.1.A1 – EST Control Module (A002): CAN Communication Failure / Connection Fault

The FENDT control module is failing to communicate properly with the engine control module over the Transmission Bus (G-BUS). The immediate effect of this fault is reduced engine power / torque limitation.

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1. 1

   Connect the diagnostic adapter box, turn the ignition 'ON', and check if the fault is active or stored

2. 2

   Inspect the fuses for the EDC control module located on Fuse Board A013 (a blown fuse cuts power to the EDC, triggering a communication fault)

3. 3

   Test wiring continuity on the Transmission Bus (G-BUS) CAN communication lines between the EST and EDC modules (specifically test EST A002 Pin 4/Connector X031 to EDC A021 Pin 11/Connector X048, and EST A002 Pin 5/Connector X031 to the EDC module)

4. 4

   Check the CAN-Bus wiring for any short circuits to earth or chafed wires

5. 5

   Use Serdia diagnostics or FENDIAS to check for level converter faults or to verify module identification

1. 1

   Power down tractor

   Turn off the tractor and disconnect the battery before repairing wiring or replacing modules.

2. 2

   Replace blown fuse

   If the diagnostic checks reveal a blown fuse on Fuse Board A013, replace the fuse. If the fuse blows again immediately, trace the EDC power wire for a short to ground.

3. 3

   Repair wiring harness

   If continuity is broken between Connector X031 and Connector X048, locate the break in the wiring harness. Repair the CAN lines using appropriate twisted-pair repair techniques and OEM sealed connectors (e.g., AMP Superseal).

4. 4

   Replace control module

   If the wiring, power, and grounds are all intact, the fault lies internally within either the EDC Control Module (A021/A022) or the EST Control Module (A002). Replace the faulty module.

5. 5

   Reprogram module

   If a control module is replaced, End-of-Line (EOL) reprogramming will be necessary to pair the new module with the Tractor Management System (TMS).