Isuzu N 2008 Series Workshop Manual page 247

1A-244 Engine Control System (4JJ1)
Step
Important: The APP sensor 1 may be damaged if
the sensor signal circuit is shorted to a voltage
source.
1. Test the signal circuit between the ECM (pin
63 of J14) and the APP sensor (pin 5 of B5)
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 APP sensor 1 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 APP sensor (pin
6 of B5) 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
APP sensor (pin 6 of B5).
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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 41 of J14).
4. Repair the connection(s) as necessary.
Did you find and correct the condition?
Replace the APP sensor. Refer to Accelerator
Pedal Sensor in Section 1I Engine Speed Control
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System.
Did you complete the replacement?
Important:
programmed and learned.
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Replace the ECM. Refer to ECM Replacement.
Did you complete the replacement?
1. Reconnect
harness connector(s).
2. Clear the DTCs with a scan tool.
3. Turn OFF the ignition for 30 seconds.
4. Start the engine.
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5. Fully depress and release the accelerator
pedal while observing the APP Sensor 1
parameter with the scan tool.
Does the scan tool indicate more than the specified
value during depressing or releasing the pedal?
Observe the DTC Information with a scan tool.
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Are there any DTCs that you have not diagnosed?
Action
Replacement ECM
all previously disconnected
Value(s)
—
—
—
—
—
must be
—
4.9 volts
—
Yes
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
Go to Step 3 Go to Step 14
Go to DTC List
No
—
—
System OK