Isuzu 2008MY N Series Workshop Manual page 337

1A-334 Engine Control System (4HK1)
Step
1. Turn OFF the ignition.
2. Disconnect the ECM J-14 harness connector.
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3. Turn ON the ignition, with the engine OFF.
Is the exhaust brake indicator lamp OFF?
1. Turn OFF the ignition.
2. Disconnect the ECM J-14 harness connector.
3. Remove the Meter (10A) fuse that supplies
voltage to the exhaust brake indicator lamp.
4. Turn ON the ignition, with the engine OFF.
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5. Measure the voltage from the exhaust brake
indicator lamp control circuit in the ECM
harness connector (pin 7 of J-14) 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.
4. Connect a 3-amp fused jumper wire between
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the ECM harness connector (pin 7 of J-14)
and a known good ground.
Is the exhaust
illuminated?
1. Test the control circuit between the ECM (pin
7 of J-14) and the IP cluster (pin 13 of B-106)
for an open circuit or high resistance.
13
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 IP
cluster (pin 13 of B-106).
14
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 7 of J-14).
15
2. Repair the connection(s) as necessary.
Did you find and correct the condition?
Repair the short to ground between the ECM (pin 7
of J-14) and the IP cluster (pin 13 of B-106).
16
Did you complete the repair?
Repair the short to battery or ignition voltage
between the ECM (pin 7 of J-14) and the IP cluster
17
(pin 13 of B-106).
Did you complete the repair?
Repair or replace the IP cluster. Refer to Instrument
Panel (IP) Cluster in Section 9E Instrumentation /
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Driver Info.
Did you complete the repair or replacement?
Action
brake indicator lamp
Value(s) Yes
—
Go to Step 19
1 volt
Go to Step 12
—
Go to Step 15
—
Go to Step 20
—
Go to Step 20
—
Go to Step 20
—
Go to Step 20
—
Go to Step 20
—
Go to Step 20
No
Go to Step 16
Go to Step 17
Go to Step 13
Go to Step 14
Go to Step 18
Go to Step 19
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—
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