Isuzu N 2008 Series Workshop Manual page 156

Step
1. Turn OFF the ignition.
2. Disconnect the ECM J14 harness connector.
5
3. Turn ON the ignition, with the engine OFF.
Is the glow plug lamp OFF?
1. Remove the Meter (10A) fuse that supplies
voltage to the glow plug lamp.
2. Turn ON the ignition, with the engine OFF.
3. Measure the voltage from the glow plug lamp
6
control circuit in the ECM harness connector
(pin 11 of J14) to a known good ground.
Is the voltage less than the specified value?
1. Turn OFF the ignition.
2. Reinstall the Meter (10A) fuse.
3. Turn ON the ignition, with the engine OFF.
7 4. Connect a 3-amp fused jumper wire between
the ECM harness connector (pin 11 of J14)
and a known good ground.
Is the glow plug lamp illuminated?
1. Turn OFF the ignition.
2. Remove the IP cluster.
3. Connect a test lamp between the ignition
voltage feed circuit of the IP cluster harness
8
connector (pin 2 of B105) and a known good
ground.
4. Turn ON the ignition, with the engine OFF.
Does the test lamp illuminate?
1. Test the control circuit between the ECM (pin
11 of J14) and the IP cluster (pin 5 of B106) for
an open circuit or high resistance.
9
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
IP cluster (pins 2 of B105 and 5 of B106).
10
2. Repair the connection(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
ECM (pin 11 of J14).
11
2. Repair the connection(s) as necessary.
Did you find and correct the condition?
Repair the short to ground between the ECM (pin
11 of J14) and the IP cluster (pin 5 of B106).
12
Did you complete the repair?
Repair the short to battery or ignition voltage
between the ECM (pin 11 of J14) and the IP cluster
13
(pin 5 of B106).
Did you complete the repair?
Action
Engine Control System (4JJ1)
Value(s) Yes
—
Go to Step 6
1 volt
Go to Step 7
—
Go to Step 11
—
Go to Step 9
—
Go to Step 17
—
Go to Step 17
—
Go to Step 17
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Go to Step 17
—
Go to Step 17
1A-153
No
Go to Step 12
Go to Step 13
Go to Step 8
Go to Step 14
Go to Step 10
Go to Step 15
Go to Step 16
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