New Holland Workmaster 50, Service Manual

Page: 1005 / 1067

Electrical systems - FAULT CODES
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 To Value
X-9011 pin 2 Chassis ground There should be no continuity.
X-9011 pin 2 X-9011 pin 3 There should be no continuity.
X-9011 pin 2 X-9011 pin 6 There should be no continuity.
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 To Value
X-9001 pin A34 All pins in connector X-9001 There should be no continuity.
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