
RENR5622 121
Troubleshooting Section
Expected Result:
Cat ET displays “Short” when the wire jumper is
shorted to engine ground. Cat ET displays “Open”
when the signa
l wire for the injector is removed from
the ECM connector.
Results:
•
OK – The ECM is operating properly. The problem
is in the wirin
g between the ECM and the injector
connector.
Repair: Repa
ir the harness or the connector. Refer
to the diagnostic functional test Troubleshooting,
“Inspecting Electrical Connectors”. Verify that the
repair elimi
nates the problem.
STOP.
•
Not OK – The ECM did not detect the open or the
short.
Repair: Replace the ECM. Refer to
Troubleshooting, “Replacing the ECM”.
Verify that
the problem is resolved.
STOP.
Test Step 7. Mea sure the Resistance of
the Injector S olenoid
Personal injury can result from high v oltage.
The Electronic Control Module produces high
voltage.
Make sure the Electronic Control Module is not
powered and the fuel injector solenoids are dis-
connected before proceeding.
A. Measure the solenoid resistance between pin 1
and pin 2 at the injector connectors.
B. Record the measured resistance for each
solenoid.
Expected Result:
The resistance is 1.07 ± 0.1 Ohms.
Results:
•
OK – The resistance is 1.07 ± 0.1 Ohms.
Repair: The problem may be intermittent. If the
problem is inte
rmittent, refer to the diagnostic
functional test Troubleshooting, “Inspecting
Electrical Connectors”. Verify that the repair
eliminates th
e problem.
STOP.
•
Not OK – The resistance is not 1.07 ± 0.1 Ohms.
Repair: Repla
ce the injector. If the new injector has
a trim code that is different from the old injector,
changethetrimcodeintheECM.
STOP.
i02301588
Inspecting Electrical
Conne cto rs
SMCS Code: 1901-038
System Opera
tion Description:
Most electrical problems are caused by poor
connection
s. The following procedure will assist in
detecting problems with connectors and with wiring.
If a problem is found, correct the condition and verify
that the pro
blem is resolved.
Intermittent electrical problems are sometimes
resolved by
disconnecting and reconnecting
connectors. It is very important to check for diagnostic
codes immediately before disconnecting a connector.
Also check
for diagnostic codes after reconnecting
the connector. If the status of a diagnostic code is
changed due to disconnecting and reconnecting a
connecto
r, there are several possible reasons. The
likely reasons are loose terminals, improperly crimped
terminals, moisture, corrosion, and inadequate
mating of
a connection.
Follow these guidelines:
•
Always use a 1U-5804 Crimp Tool to service
Deutsch HD and DT connectors. Never solder the
terminal
s onto the wires. Refer to “SEHS9615,
Servicing Deutsch HD and DT Style Connectors”.
•
Always u
se a 147-6456 Wedge Removal Tool to
remove wedges from DT connectors. Never use a
screwdriver to pry a wedge from a connector.
•
Always use a breakout harness for a voltmeter
probe or a test light. Never break the insulation
of a wire
in order to access to a circuit for
measurements.
•
If a wire
is cut, always install a new terminal for
the repair.