Isuzu 2008MY N Series Workshop Manual page 125

1A-122 Engine Control System (4HK1)
Step
Important: The intake throttle position sensor may
be damaged if the sensor signal circuit is shorted to
a voltage source.
1. Test the signal circuit between the ECM (pin
85 of E-12) and the intake throttle valve (pin 5
of E-16) 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 intake throttle position 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 109 of E-12) and the intake throttle
valve (pin 4 of E-16) 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 poor
connections at the harness connector of the
intake throttle valve (pin 4 of E-16).
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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 109 of E-12).
4. Repair the connection(s) as necessary.
Did you find and correct the condition?
Replace the intake throttle valve. Refer to Intake
Throttle Valve in Section 1B Engine Mechanical.
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Did you complete the replacement?
Important:
programmed and learned.
12
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. Operate the vehicle within the Conditions for
Running the DTC. You may also operate the
vehicle
observed from the Freeze Frame/ Failure
Records.
Did the DTC fail this ignition?
Action
Replacement ECM
all previously disconnected
within the conditions
Value(s)
—
—
—
—
—
must be
—
—
that you
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 2 Go to Step 14
No