New Holland WorkMaster 50 Service Manual page 1005

DTC 68D-04-Throttle valve actuator control circuit low side shorted
to ground
Control Module : ECU
Context:
The Engine Control Unit (ECU) A-9000 monitors the throttle valve actuator Z-9001 output 1 and output 2 h-bridge
circuits. If the ECU A-9000 detects a short to ground condition in the throttle valve actuator Z-9001 output 2 h-bridge
circuit, this fault will occur.
Cause:
The ECU A-9000 has detected a short to ground condition in the throttle valve actuator Z-9001 output 2 h-bridge
circuit.
Possible failure modes:
1. Faulty throttle valve actuator Z-9001 wiring, short to ground condition.
2. Faulty throttle valve actuator Z-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 5.
2. Check the throttle valve actuator Z-9001 output 2 h-bridge engine harness (EN) wiring for a short to ground con-
dition.
Disconnect the engine harness (EN) from the throttle valve actuator Z-9001 at connector X-9011.
With the key in the OFF position, use a multimeter to perform the following continuity check on the engine harness
(EN) side :
From
X-9011 pin 2
X-9011 pin 2
X-9011 pin 2
A. If there is continuity, there is a short circuit in the throttle valve actuator Z-9001 output 2 h-bridge circuit. Locate
and repair the shorted conductor.
B. If there is no continuity, leave connector X-9011 disconnected and continue to Step 3.
3. Check the throttle valve actuator Z-9001 output 2 h-bridge engine harness (EN) wiring for a short to ground con-
dition.
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-9001 pin A34
Electrical systems - FAULT CODES
To
Chassis ground
X-9011 pin 3
X-9011 pin 6
To
All pins in connector X-9001
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Value
There should be no continuity.
There should be no continuity.
There should be no continuity.
Value
There should be no continuity.