Engine Control System 1A-187
Diagnostic Aids
Poor connection or damaged harness may cause
intermittents. Check for the following conditions and, if
the fault is detected, repair or replace the faulty portion.
• Poor connection at ECM: Inspect harness
connectors for backed-out pins, improper mating,
broken locks, improperly formed or damaged pins,
and poor pin-to-wire connection.
• Damaged harness: Inspect the wiring harness for
rubbed-through wire insulation or wire broken
inside the insulator. If the harness appears to be
OK, observe the display on Tech 2 while moving
connectors and wiring harnesses related to the
sensor. A change in the display will indicate the
location of the fault.
Test Description
Number(s) below refer to the step number(s) on the
Diagnostic Chart.
3. If the DTC is not detected, the possible cause is
intermittent (intermittent fault).
6. If pins are jumpered and the resistance reads
∞
Ω
,
the cause is open wiring. If pins are not jumpered and
the resistance reads 0
Ω
, the cause is short.
Step
Action
Value(s)
Yes
No
1
Perform the "On-Board Diagnostic (OBD)
System Check".
Was the OBD System Check performed?
—
Go to Step 2
Refer to OBD
System Check
and go to Step 2
2
Check the injector connector for installation
and, if mounted improperly, connect it
certainly.
Is the action complete?
—
Go to Step 3
—
3
Review the DTC.
1.
Using Tech 2, check and store the DTC.
2.
Clear the DTC.
3.
Perform test run and review the DTC.
Is DTC159 detected?
—
Go to Step 4
Refer to
Diagnostic Aids
4
Check the common 2 injector drive circuit for
+B short.
1.
Starter switch "OFF".
2.
Disconnect the ECM.
3.
At the ECM connector pins, measure the
resistance.
Was the resistance within range?
Pins 4/5-109/
114/115/116:
∞
Ω
Go to Step 6
Go to Step 5
5
Repair or replace the faulty harness.
Is the action complete?
—
Verify repair and
go to Step 15
—
6
Check the common 2 injector drive circuit
(ECM to intermediate connector) for open
wiring or short.
1.
Disconnect the ECM.
2.
Disconnect the injector connector.
3.
Jumper the injector connector and
measure the resistance at the ECM
connector.
Was the resistance within range?
Pins 4-
ground
(jumpered:
pins 2/3-
ground): 0
Ω
(not jumpered):
∞
Ω
Pins 5-
ground
(jumpered:
pins 2/3-
ground): 0
Ω
(not jumpered):
∞
Ω
Pins 4-5
(not jumpered):
0
Ω
Go to Step 7
Go to Step 10