Isuzu 2008MY N Series Workshop Manual page 109

1A-106 Engine Control System (4HK1)
Step
Important: The boost pressure sensor may be
damaged if the sensor signal circuit is shorted to a
voltage source.
1. Test the signal circuit between the ECM (pin
91 of E-12) and the boost pressure sensor
(pin 1 of E-24) 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 boost pressure 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 boost pressure
sensor (pin 2 of E-24) 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
boost pressure sensor (pin 2 of E-24).
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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 boost pressure sensor. Refer to Boost
Pressure Sensor in Section 1J Induction.
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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)
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must be
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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
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