Isuzu 2008MY N Series, Руководство по ремонту

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1A-52 Engine Control System (4HK1)
6
Repair the open in the ignition voltage circuit to the
ECM.
Did you complete the repair?
—
Go to Step 18
—
7
1. Turn OFF the ignition.
2. Disconnect the scan tool from the DLC if
connected.
3. Measure the resistance across the CAN Low
and High circuits by probing the DLC (pins 6
and 14 of B-31).
Is the resistance within the specified value
(parallel resistance of the 120
Ω
resistor in the
ECM and the 120
Ω
CAN resistor should be
60
Ω
)?
50 to 70
Ω
Go to Step 9 Go to Step 8
8
1. Turn OFF the ignition.
2. Disconnect the ECM harness connector.
3. Inspect for an intermittent, for poor
connections and corrosion at the harness
connector of the ECM (pins 58 and 78 of J-
14).
4. Test the CAN Low and High serial data circuits
between the ECM (pins 58 and 78 of J-14)
and the DLC (pins 6 and 14 of B-31) for the
following conditions:
• An open circuit
• A short circuit each other
• High resistance
5. Repair the connection(s) or circuit(s) as
necessary.
Did you find and correct the condition?
—
Go to Step 18 Go to Step 17
9
1. Test the CAN Low and High serial data circuits
between the DLC (pins 6 and 14 of B-31) and
the ECM (pins 58 and 78 of J-14) or resistor
(pins 1 and 2 of B-302) for the following
conditions:
• A short to ground
• A short to voltage
2. Repair the circuit(s) as necessary.
Did you find and correct the condition?
—
Go to Step 18 Go to Step 10
10
Notice: An open in a ground circuit at the ECM will
not cause a loss of communication.
1.
Check ECM ground for corrosion and
tightness.
2. Clean or tighten grounds as necessary.
Did you find and correct the condition?
—
Go to Step 18 Go to Step 11
Step Action Value(s) Yes No
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