New Holland WorkMaster 50 Service Manual page 729

DTC 11C-02-Water in fuel sensor or sensor circuit failure
Control Module : ECU
NOTE: This fault code is for the Water in Fuel switch with black connector housing.
Context:
The water in fuel switch S-9102 provides a diagnostic self-test signal (less than 3.9 V for 2.5 s +/- 20%) at key-ON.
If the Engine Control Unit (ECU) A-9000 does not sense the diagnostic self-test signal, this fault will occur and there
will be no monitoring of water content in the fuel supply.
Cause:
The ECU A-9000 has not received an acceptable water in fuel switch S-9102 self-test signal.
Possible failure modes:
1. Faulty water in fuel switch S-9102 circuit wiring, damaged.
2. Faulty water in fuel switch S-9102, internal failure.
3. Faulty ECU A-9000, software.
Solution:
1. Verify this fault code is still present and in an active state.
Use the Easy Engine software provided on the Electronic Service Tool (EST) to check the fault status.
A. If the fault is still present and active, continue with Step 2.
B. If the fault is no longer present or is in an inactive state, Continue with Step 7.
2. Use the EST to check for related faults that may have caused this fault to occur.
A. If any other faults that may have caused this fault to occur are active, resolve those faults first and then return
to this fault.
B. If no other faults are active,continue with Step 3.
3. Check the water in fuel switch S-9102 for the initial self-test voltage pulse.
Carefully back probe the water in fuel switch S-9102 at connector X-9125.
With the help of an assistant, use a multimeter to perform the following test at Key-ON:
From
X-9125 pin 1
NOTE: The signal line should switch to battery voltage after the self-test period.
A. If the self-test is successful, continue with Step 4.
B. If the self-test is not successful, the water in fuel switch S-9102 has failed internally. Replace the switch.
4. Check for open, short and grounded circuit conditions in the water in fuel switch S-9102 circuit.
Disconnect the water in fuel switch S-9102 at connector X-9125.
Disconnect the vehicle (VE) harness from the ECU A-9000 at connector X-9102.
With the key switch in the OFF position, use a multimeter to perform the following tests, on the vehicle (VE) harness
from :
Electrical systems - FAULT CODES
To
Chassis ground
47866583_ 02/12/2015
55.12 [55.DTC] / 8
Value
There should be less than 3.9 V for
2.5 s +/- 20%.