
RENR9348-01 151
Troubleshooting Section
Test Step 5. Check the Operation of the
ECM
A. Fabricate two jumper wires that are long enough
to create a short circuit between terminal locations
at the ECM conn
ector. Crimp a connector socket
to one end of each of the jumper wires.
B. Disconnect t
he J1/P1 ECM connectors.
C. Remove the wires from terminal locations P1-5
(digital ret
urn) and P1-22 (auto/manual switch) at
the ECM connector. Install the jumper wires into
these terminal locations.
D. Connect the J1/P1 ECM connector.
E. Rest ore the e
lectrical power to the ECM.
Note: Ensure that the loose ends of the jumper wires
are creating
an open circuit at the ECM. Do not allow
the jumper wires to contact a ground source or each
other during the test.
F. Observe the status of the “Ether Switch” on Cat
ET.
G. Connect the loose ends of the jumper wire in
order to create a short in the circuit at the ECM
connector
.
H. Observe the status of the “Ether Switch” on Cat
ET.
I. Restore the wiring to the original configuration.
Expected Result:
The status
of the “Ether Switch” changes from “Auto”
to “Manual” during the test.
Results:
•
OK – The status of the “Ether Switch” changes
from “Auto
”to“Manual”duringthetest.TheECM
is OK. The problem is in the harness between the
ECM and the auto/manual switch. The problem
maybeina
connector. Repair the harness and/or
the connector. Replace parts, if necessary. Verify
that the original problem is resolved.
•
Not OK – The status for the auto/manual switch
does not change from “Auto” to “Manual” during
the test
.
Repair: The ECM is not reading the switch input.
Replace
the ECM. Refer to Troubleshooting,
“Replacing the ECM”.
STOP.
Test Step 6. C heck the Voltage at the
Starting Aid Solenoid
A. Disconnect the connector for the starting aid
solenoid.
B. Connect a voltmeter between terminals 1 and 2
on the harness side of the connector.
C. Restore the electrical power to the ECM.
D. Select the “O
verride Parameters” option from the
“Diagnostic Tests” on Cat ET.
E. Activate the
override for “Ether Injection”.
F. Measure the voltage at the connector for the
starting aid
solenoid valve.
Note: The ether override will activate the solenoid for
ten seconds.
The measurement must be taken within
this time period.
G. Remove elec
trical power from the ECM.
H. Restore the wiring to the original configuration.
Expected Result:
The voltage
at the ether solenoid is 24 ± 3 VDC.
Results:
•
OK – The voltage at the connector for the ether
solenoid is 24 ± 3 VDC.
Repair: Control input voltage is present at the
connector for the starting aid solenoid. There is a
problem wit
h the ether solenoid. Replace the ether
solenoid.
STOP.
•
Not OK – The voltage at the ether solenoid is not
24 ± 3 VDC. T
here is a problem in the harness
between the ECM and the starting aid solenoid.
There may be a problem with the ECM. Proceed
to Test Ste
p7.
Test Step 7. Check the Operation of the
ECM
A. Fabricate two jumper wires that are long enough
to create a test circuit at the ECM connector.
Crimp a co
nnector socket to one end of each of
the jumper wires.
B. Disconne
ct the J1/P1 ECM connectors.
C. Remove the wires from terminal locations P1-18
(ether so
lenoid) and P1-20 (solenoid return) at the
ECM connector. Install a wire jumper into each of
these terminal locations.