Isuzu 4HL1, Workshop Manual

Page: 190 / 267

1A-188 Engine Control System
7
Check the intermediate connector for fault.
1. Disconnect ECM side and injector side
connectors from the intermediate
connector.
2. Remove the intermediate connector from
the engine block.
3. Jumper the intermediate connector that
was connected to the injectors and
measure the resistance at the
intermediate connector that was
connected to the ECM.
Was the resistance within range?
Pins 1-2/3/4
(jumpered:
pins 1-2/3/4):
0
Ω
(not jumpered):
∞ Ω
Pins 2-3/4
(jumpered:
pins 2-3/4):
0
Ω
(not jumpered):
∞ Ω
Pins 3-4
(jumpered:
pins 3-4): 0
Ω
(not jumpered):
∞ Ω
Go to Step 9 Go to Step 8
8
Replace the intermediate connector.
Is the action complete?
—
Go to Step 16 —
9
Check the common 2 injector drive circuit
(intermediate connector to injector) for open
wiring or short.
1. Disconnect the injector side connectors
from the intermediate connector.
2. Disconnect harnesses from injectors for
cylinders 2 and 3.
3. Measure the resistance between injector
terminal and connector pin as well as
between connector pins.
Was the resistance within range?
Cylinder 2
-pins 2:
0
Ω
Cylinder 3
-pins 3:
0
Ω
Pins 2-3:
∞ Ω
Go to Step 11 Go to Step 10
10
Repair or replace the faulty harness.
Is the action complete?
—
Verify repair and
go to Step 16 —
11
Measure the resistance between injector
terminals (resistance of coil) for cylinders 2
and 3.
Was the resistance within range?
0.4
Ω
Go to Step 14 Go to Step 12
12
Repair or replace the faulty injector(s).
Is the action complete?
—
Go to Step 13 —
13
Check DTC159 will not be set again.
1. Restore the vehicle.
2. Using Tech 2, clear the DTC.
3. Bleed the air from the fuel system.
4. Perform test run and review the DTC.
Is DTC159 detected?
—
Refer to
Diagnostic Aids
and go to Step 2
Repair is
complete
14
Review the DTC.
1. Restore the vehicle.
2. Using Tech 2, clear the DTC.
3. Perform test run and review the DTC.
Is DTC159 detected?
—
Go to Step 15
Refer to
Diagnostic Aids
Step Action Value(s) Yes No