
112 RENR9348-01
Troubleshooting Section
D. Check the allen head screw on each ECM
connector for t
he proper torque. Refer to
Troubleshooting, “Electrical Connectors - Inspect”
for the correct torque values.
Expected Result:
All connector
s, pins, and sockets are completely
coupled and/or inserted, and the harness and wiring
are free of corrosion, of abrasion or of pinch points.
Results:
•
OK – The harne
sses and the wiring appear to be
OK. Proceed to Test Step 2.
•
Not OK – There
is a problem with the connectors
and/or the wiring.
Repair: Repa
ir the wiring and connectors or
replace the wiring or the connectors. Ensure that
all of the seals are properly connected. Verify that
the repair e
liminates the problem.
STOP.
Test Step 2. Check the Supply Voltage at
the Sensor Connector
A. Disconnect
the coolant level sensor at the sensor
connector.
B. Restore ele
ctrical power to the ECM.
C. Measure the voltage between terminals A (sensor
supply) an
d B (sensor return) at the harness
connector for the coolant level sensor.
D. Remove ele
ctrical power from the ECM.
Expected Result:
The voltage measurement is 8.0 ± 0.4 VDC.
Results:
•
OK – The voltage measurement is 8.0 ± 0.4 VDC.
The supply
voltage is reaching the sensor. Proceed
to Test Step 3.
•
Not OK – Th
e voltage measurement is not 8.0 ±
0.4 VDC.
Repair: T
he digital sensor supply voltage is
not reaching the sensor. There is a problem in
the circuit for the digital sensor supply. Refer to
Troubles
hooting, “Digital Sensor Supply Circuit -
Te s t ”.
STOP.
Test Step 3. Check the Coolant Level
Pressurized System: Hot coolant can cause seri-
ous burns. To open the cooling system filler cap,
stop the engine and wait until the cooling system
components are cool. Loosen the cooling system
pressure cap slowly in order to relieve the pres-
sure.
A. Remove electrical power from the ECM.
Note: Allow the engine to cool prior to removal of the
cooling system pressure cap.
B. Check the coolant level. Refer to the Operation
and Maintenance Manual for the proper procedure
to check the coolant level.
Expected Result:
The coolant is at the proper level.
Results:
•
OK – The coolant is at the proper level. Proceed
to Test Step 4.
•
Not OK – The coolant level is low.
Repair: Add coolant according to the procedure in
the Operation and Maintenance Manual.
There may be a leak in the cooling system. Identify
the source of the coolant leak. Repair the leak.
STOP.
Test Step 4. Disconnect the C oolant
Level Sensor and Monitor th e Status f or
“Coolant Level”
A. Connect the Cat ET to the service tool connector.
Refer to Troubleshooting, “Electronic Service
To o l s” .
B. Disconnect the harness connector for the coolant
level sensor.
C. Restore electrical power to the ECM.
D. Monitor the status of “Coolant Level” on Cat ET.
Note: Wait at least 30 seconds for activation of the
status indicator.
E. Remove electrical power from the ECM.