
114 RENR9348-01
Troubleshooting Section
The correct resistance measurement is a short
circuit.
Remove the jumper wire. Leave the sensor connector
disconnected
.
Expected Result:
The measurement indicates that a short circuit exists
for the signal wire.
Results:
•
OK – The measur
ement indicated a short circuit.
There is not an open circuit in the harness wire for
the sensor signal. Proceed to Test Step 7.
•
Not OK – The measurement did not indicate a
short circuit.
Repair: There is an open circuit or excessive
resistance in the harness or the connectors. Repair
the wire and/
or the connector, when possible.
Replace damaged parts, if necessary.
STOP.
Test Step 7. Check the Harness Wiring
for a Short Circuit
A. Remove electrical power from the ECM.
B. Disconnect
theJ1/P1andtheJ2/P2ECM
connectors. Also, disconnect the connector for the
coolant level sensor.
C. Measure the resistance between the points that
are listed in Table 20.
Note: Wiggle the harness during the following
measurements in order to reveal an intermittent
condition
.
Table 20
Resistance Measurements for the C oolant
Level Circuit
Connector and
Terminal
Terminal
All of the terminals on the P1
connector
All of the other terminals on
the P2 con
nector
P2-39 (Coolant level)
Engine ground stud
Expected Result:
Each check of the resistance indicates an open
circuit.
Results:
•
OK – Each check of the resistance indicates an
open circuit. There is not a short circuit to another
wire in the har
ness. Proceed to Test Step 8.
•
Not OK – At least one check of the resistance
does not indic
ate an open circuit. There is a short
to another wire in the harness. The problem may
be with a connector.
Repair: Repair the wire and/or the connector, when
possible. Replace damaged parts, if necessary.
Verify that t
he problem is resolved.
STOP.
Test Step 8. Check the Operation of the
ECM
A. Remove the wi
res from terminal locations P1-5
(sensor return) and P2-39 (coolant level).
B. Fabricate a
jumper wire that is long enough to
provide a test circuit between these two terminals
at the P1 and the P2 ECM connectors. Crimp
connector s
ockets to each end of the jumper wire.
C. Install one end of the jumper wire into terminal
location P
1-5. Install the other end of the jumper
wire into terminal location P2-39. Connect the P1
and P2 ECM connectors to the E CM.
D. Restore electrical power to the ECM.
E. Use Cat ET t
o monitor the status for “Coolant
Level”. Remove the jumper wire and check the
status again.
Note: Wait at least 30 seconds for activation of the
status indicator.
F. Remove electrical power from the ECM.
Restore a
ll wiring to the original configuration.
Expected Result:
The status is “LOW” when the jumper wire is not
connected. The status is “OK” when the jumper wire
is connec
ted.
Results:
•
OK – The status is “LOW” when the jumper wire is
not connected. The status is “OK” when the jumper
wire is co
nnected.