Isuzu N 2008 Series Workshop Manual page 290

Step
1. Turn OFF the ignition.
2. Disconnect the PTO throttle sensor harness
connector.
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3. Turn ON the ignition, with the engine OFF.
Is the PTO Remote Throttle Sensor parameter less
than the specified value?
Connect a test lamp between the low reference
circuit (pin 1 of J39) and battery voltage.
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Does the test lamp illuminate?
Important: The PTO throttle sensor may be
damaged if the sensor signal circuit is shorted to a
voltage source.
1. Test the signal circuit between the ECM (pin
70 of J14) and the PTO throttle sensor (pin 2
of J39) for the following conditions:
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• A short to battery or ignition voltage
• A short to any 5 volts reference
2. Repair the circuit(s) as necessary.
Did you find and correct the condition?
Notice: The PTO throttle sensor shares the low
reference circuit with other sensors. A fault
condition in the low reference circuit may set DTCs
on sensors that share this circuit.
1. Test the low reference circuit between the
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ECM (pin 41 of J14) and the PTO throttle
sensor (pin 1 of J39) for an open circuit or high
resistance.
2. Repair the circuit(s) as necessary.
Did you find and correct the condition?
1. Inspect for an intermittent and for a poor
connection at the harness connector of the
PTO throttle sensor (pin 1 of J39).
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2. Repair the connection(s) as necessary.
Did you find and correct the condition?
1. Turn OFF the ignition.
2. Disconnect the ECM harness connector.
3. Inspect for an intermittent and for a poor
connection at the harness connector of the
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ECM (pin 70 of J14).
4. Repair the connection(s) as necessary.
Did you find and correct the condition?
Replace the PTO throttle sensor.
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Did you complete the replacement?
Important: Replacement
programmed and learned.
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Replace the ECM. Refer to ECM Replacement.
Did you complete the replacement?
Action
ECM must
Engine Control System (4JJ1)
Value(s)
0.1 volts
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be
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Yes
Go to Step 6 Go to Step 7
Go to Step 9 Go to Step 8
Go to Step 13 Go to Step 12
Go to Step 13 Go to Step 10
Go to Step 13 Go to Step 11
Go to Step 13 Go to Step 12
Go to Step 13
Go to Step 13
1A-287
No
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