
142 RENR5622
Troubleshooting Section
g01094844
Illustration 71
Sensor co nnector
(Pin A) Sensor sup ply
(Pin B) Sensor ret u rn
(Pin C) Signal
Test Step 1. Inspect Electrical Connector s
and Wiring
A. Remove power from the ECM.
B. Thoroughly inspect the J1/P1 ECM connector
and the J2/P2 ECM connector. Inspect all of the
connectors that are associated with the circuit.
Refer to Troubleshooting, “Inspecting Electrical
Connectors” for details.
C. Perform a 45 N (10 lb) pull test on each of the
wires in the ECM connectors that are associated
with the circuit.
D. Check the ECM connector (allen head screw)
for the proper torque. Refer to Troubleshooting,
“Inspecting Electrical Connectors” for details.
E. Check the harness and wiring for abrasion and for
pinch points from the sensors back to the ECM.
Expected Result:
All connectors, pins and sockets are completely
coupled and/or inserted and the harness and wiring
are free of corrosion, of abrasion and of pinch points.
Results:
•
OK – The harness and connectors appear to be
OK. Proceed to Test Step 2.
•
Not OK – There is a problem with the connectors
and/or wiring.
Repair: Repair the connectors or wiring and/or
replace the con
nectors or wiring. Ensure that all of
thesealsareproperlyinplaceandensurethatthe
connectors are completely coupled.
Verify that the repair eliminates the problem.
STOP.
Test Step 2. Check fo r Active Diagnostic
Codes
A. Connect Caterpillar Electronic Technician (ET) to
the service tool connector.
B. Restore power to the ECM.
C. Monitor the a
ctive diagnostic code screen on
Cat ET. Check and record any active diagnostic
codes. Look for the following diagnostic codes:
•
262-03
•
262-04
•
263-03
•
263-04
Note: Wait a
t least 30 seconds in order for the
diagnostic codes to become active.
Expected Re
sult:
No diagnostic codes are active.
Results:
•
OK – No diagn
ostic code is active.
Repair: The problem is no longer present. If the
problem is i
ntermittent, refer to Troubleshooting,
“Inspecting Electrical Connectors”.
STOP.
•
Not OK – Either the 262-03 or 262-04 diagnostic
code is acti
ve at this time. Proceed to Test Step 3.
•
Not OK – Either the 263-03 or 263-04 diagnostic
code is act
ive at this time. Proceed to Test Step 5.
Test Step 3. Disconnect the 5 Volt
Sensors wh ile you Mon itor the Active
Diagnostic Codes
A. Monitor the active diagnostic code screen on Cat
ET while you disconnect each 5 Volt sensor at
the senso
r connector. Check for an active 262-03
code or an active 262-04 code.