Isuzu N 2008 Series Workshop Manual page 265

1A-262 Engine Control System (4JJ1)
Step
Important: The BARO sensor may be damaged if
the sensor signal circuit is shorted to a voltage
source.
1. Test the signal circuit between the ECM (pin
71 of J14) and the BARO sensor (pin 1 of
B121) 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 BARO 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 60 of J14) and the BARO sensor
(pin 1 of B121) 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
BARO sensor (pin 1 of B121).
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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 60 of J14).
4. Repair the connection(s) as necessary.
Did you find and correct the condition?
Replace the BARO sensor. Refer to BARO Sensor
Replacement.
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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. 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?
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
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
Go to DTC List
No
—
—
System OK