Isuzu N 2008 Series Workshop Manual page 245

1A-242 Engine Control System (4JJ1)
Step
Connect a 3-amp fused jumper wire between the 5
volts reference circuit and the signal circuit (pins 4
and 5 of B5).
5
Is the APP Sensor 1 parameter more than the
specified value?
Notice: The APP sensor 1 shares the 5 volts
reference circuit with other sensors. A fault
condition in the 5 volts reference circuit may set
DTCs on sensors that share this circuit.
1. Test the 5 volts reference circuit between the
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ECM (pin 42 of J14) and the APP sensor (pin
4 of B5) for an open circuit or high resistance.
2. Repair the circuit(s) as necessary.
Did you find and correct the condition?
1. Test the signal circuit between the ECM (pin
63 of J14) and the APP sensor (pin 5 of B5)
for the following conditions:
• An open circuit
• A short to ground
7
• A short to the low reference circuit
• High resistance
2. Repair the circuit(s) as necessary.
Did you find and correct the condition?
1. Inspect for an intermittent and for poor
connections at the harness connector of the
APP sensor (pins 4 and 5 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 poor
connections at the harness connector of the
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ECM (pins 42 and 63 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
10
System.
Did you complete the replacement?
Important:
programmed and learned.
11
Replace the ECM. Refer to ECM Replacement.
Did you complete the replacement?
Action
Replacement ECM
Value(s)
4.5 volts
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must be
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Yes
Go to Step 8 Go to Step 7
Go to Step 12 Go to Step 9
Go to Step 12 Go to Step 9
Go to Step 12 Go to Step 10
Go to Step 12 Go to Step 11
Go to Step 12
Go to Step 12
No
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