New Holland WorkMaster 50 Service Manual page 745

DTC 134-04-Intake manifold pressure sensor voltage is lower than
expected
Control Module : ECU
Context:
The Engine Control Unit (ECU) A-9000 monitors the intake manifold pressure sensor B-9001. If the ECU A-9000
determines that the intake manifold pressure sensor B-9001 signal circuit voltage is less than 202.80 mV, this fault
will occur. If this fault is active, the intake manifold pressure value will be frozen at the last valid value for a preliminary
failure or jump to a fixed replacement value of 0.98 bar (14.21 psi) if the failure is validated.
Cause:
The ECU A-9000 has determined that the intake manifold pressure sensor B-9001 signal circuit voltage is less than
202.80 mV.
Possible failure modes:
1. Faulty intake manifold pressure sensor B-9001 wiring, short to ground condition.
2. Faulty intake manifold pressure sensor B-9001, internal failure.
3. Faulty ECU A-9000, software.
Solution:
1. Verify fault is present and active.
Use the Electronic Service Tool (EST) to check the status of this fault.
A. If the fault is present and active, continue with Step 2.
B. If the fault is no longer present or in an inactive state, the fault may be intermittent and not currently active.
Continue with Step 4.
2. Check the intake manifold pressure sensor B-9001 wiring in the engine harness (EN) for a short to ground condi-
tion.
Disconnect the engine harness (EN) from the intake manifold pressure sensor B-9001 at connector X-9003.
Disconnect the engine harness (EN) from the ECU A-9000 at connector X-9001.
With the key in the OFF position, use a multimeter to perform the following continuity check on the engine harness
(EN) side :
From
X-9003 pin 4
X-9003 pin 4
X-9001 pin A40
A. If there is continuity, there is a short circuit in the intake manifold pressure sensor B-9001 wiring in the engine
harness (EN). Locate and repair the shorted conductor.
B. If there is no continuity, leave connector X-9003 disconnected and continue to Step 3.
3. Replace the intake manifold pressure sensor B-9001.
Use the Electronic Service Tool (EST) to check the status of this fault.
A. If the fault is no longer active, return the machine to service.
B. If the fault is still active, check the ECU A-9000 for the appropriate software and re-flash, if necessary.
Electrical systems - FAULT CODES
To
Chassis ground
X-9003 pin 1
All pins in connector X-9001
47866583_ 02/12/2015
55.12 [55.DTC] / 24
Value
There should be no continuity.
There should be no continuity.
There should be no continuity.