Isuzu N 2008 Series Workshop Manual page 59

1A-56 Engine Control System (4JJ1)
Step
1. Test the battery voltage circuit between the
ECM (pins 2 and 5 of J14) and the ECM main
relay for the following conditions:
• An open circuit
12
• High resistance or a poor connection at
the ECM or ECM main relay
2. Repair the circuit(s) as necessary.
Did you find and correct the condition?
Replace the ECM main relay.
13
Did you complete the replacement?
Important:
programmed and learned.
14
Replace the ECM. Refer to ECM Replacement.
Did you complete the replacement?
1. Turn OFF the ignition.
2. Reconnect all previously disconnected fuse,
relay or harness connector(s).
3. Turn ON the ignition, with the engine OFF.
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4. Attempt to establish communication with the
ECM.
Does the scan tool communicate with the ECM?
Action
Replacement ECM
Value(s)
—
—
must be
—
—
Yes
Go to Step 15 Go to Step 14
Go to Step 15
Go to Step 15
System OK Go to Step 3
No
—
—