Isuzu 2008MY N Series Workshop Manual page 282

Step
Connect a 3-amp fused jumper wire between the 5
volts reference circuit and the signal circuit (pins 2
and 3 of B-121).
5
Is the BARO Sensor parameter more than the
specified value?
Notice: The BARO sensor 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
6
ECM (pin 61 of J-14) and the BARO sensor
(pin 3 of B-121) 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
71 of J-14) and the BARO sensor (pin 2 of B-
121) for the following conditions:
• An open circuit
• A short to ground
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• 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
BARO sensor (pins 2 and 3 of B-121).
8
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 61 and 71 of J-14).
4. Repair the connection(s) as necessary.
Did you find and correct the condition?
Replace the BARO sensor. Refer to BARO Sensor
Replacement.
10
Did you complete the replacement?
Important: Replacement
programmed and learned.
11
Replace the ECM. Refer to ECM Replacement.
Did you complete the replacement?
Action
ECM must
Engine Control System (4HK1)
Value(s)
4.5 volts
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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
1A-279
No
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