New Holland WorkMaster 50 Service Manual page 956

DTC 4D4-03-ECU internal failure - Overvoltage monitoring error
Control Module : ECU
Context:
The Engine Control Unit (ECU) A-9000 performs "shut-off paths" which deactivate all power stages relevant to fuel
injection if certain ECU A-9000 errors are detected. If an over-voltage condition is detected during this test, this fault
will occur.
Solution:
1. Check the ECU A-9000 for the appropriate software and re-flash, if necessary.
A. If the fault has been resolved, return the machine to service.
B. If the fault has not been resolved, escalate an ASIST concern.
Electrical systems - FAULT CODES
47866583_ 02/12/2015
55.12 [55.DTC] / 235