
RENR5622 73
Troubleshooting Section
Expected Result:
A 03 diagnostic code is active when the sensor
signal wire is removed from the ECM connector. A
04 diagnostic
code is active when the signal wire is
connected to engine ground.
Results:
•
OK – The ECM is operating properly. The problem
is in the wirin
g between the ECM and the connector
for the rail.
Repair: If th
e code is active for more than one
sensor, the problem is most likely in the return wire
for the sensor. Repair the return wire for the sensor
or replace th
e harness.
If the code is only active for one sensor, the
problem is mo
st likely in the signal wire for the
sensor. Repair the signal wire for the sensor.
STOP.
•
Not OK – One of the following conditions exists:
The03diagn
ostic code is not active when the
sensor signal wire is disconnected. The 04
diagnostic code is not active when the wire jumper
is shorted t
o ground.
Repair: Replace the ECM. Refer to
Troublesh
ooting, “Replacing the ECM”.
Verify that the problem is resolved.
STOP.
Test Step 7. Check the Supply Voltage at
the ECM
A. Remove electrical power from the ECM.
B. Remove th
e supply wires from P1-2 and P1-18.
Install wire jumpers into the sockets P1-2 and
P1-18.
C. Restore electrical power to the ECM.
D. Measure t
he voltage between the wire jumper in
terminal P1-2 and engine ground.
E. Measure t
he voltage between the wire jumper in
terminal P1-18 and engine ground.
F. Remove el
ectrical power from the ECM.
G. Remove the wire jumpers and replace all wires.
Expected Result:
The suppl
y voltage is 5.0 ± 0.2 VDC.
Results:
•
OK – The supply voltage is 5.0 ± 0.2 VDC. The
supply voltage at the ECM is correct. There is a
problem in the
wiring between the ECM and the
sensor connector. Check the supply wires and the
return wire for an open circuit.
Repair: Repair the connectors or wiring and/or
replace the connectors or wiring.
STOP.
•
Not OK – The su
pply voltage is not 5.0 ± 0.2 VDC.
The voltage at the ECM is not correct.
Repair: Repl
ace the ECM. Refer to
Troubleshooting, “Replacing the ECM”.
Verify that the problem is resolved.
STOP.
i02409119
Cat Data Link
SMCS Code: 19
01-038
System Operation Description:
Use this procedure to troubleshoot the Cat Data Link
if a problem is suspected with the wiring. Use this
procedure i
f any one of the diagnostic codes in Table
26 is active or easily repeated.