
138 RENR5622
Troubleshooting Section
Repair: Repair the connectors or wiring and/or
replace the con
nectors or wiring.
STOP.
•
Not OK – The supply voltage is not 8.0 ± 0.4 VDC.
The voltage at the ECM is not correct.
Repair: Replace the ECM. Refer to
Troubleshooting, “Replacing the ECM”.
Verify that th
e problem is resolved.
STOP.
Test Step 5. Check the Sensor’s Duty
Cycle at the Sensor Connector
A. Remove power
from the ECM.
B. Remove the suspect sensor’s signal wire from pin
C of the senso
r connector.
C. Reconnect the suspect sensor connector.
D. Restore power to the ECM.
E. Measure the d
uty cycle between the sensor’s
signal wire and pin B of the sensor connector.
Note: Set th
e multimeter to “VDC”. Press the “Hz”
button twice so that the % symbol is displayed.
F. Remove powe
rfromtheECM.
G. Replace the sensor’s signal wire and reconnect
the sensor.
Expected Result:
The duty cycle is between 10 to 90 percent.
Results:
•
OK – The duty cycle is correct. Proceed to Test
Step 6.
•
Not OK – The duty cycle is incorrect.
Repair: Replace the sensor. Verify that no
diagnostic codes are active for the suspect sensor
before per
manently installing the sensor.
STOP.
Test Step 6. Check the Sensor’s Duty
Cycle at the ECM
A. Remove pow
er from the ECM.
B. Remove the suspect signal wire for the sensor
from ECM connec
tor P1. Refer to Illustration 63
for the terminal locations for the ECM connector.
C. Restore power
to the ECM.
D. Measure the duty cycle between the sensor’s
signal wire an
d the sensor’s return wire.
Note: Set the multimeter to “VDC”. Press the “Hz”
button twice s
o that the % symbol is displayed.
E. Remove power from the ECM. Reconnect all
wires.
Expected Result:
Thedutycycleisbetween10to90percent.
Results:
•
OK – The duty cycle is correct.
Repair: Replace the ECM. Refer to the diagnostic
procedure T roubleshooting, “Replacing the ECM”.
STOP.
•
Not OK – The du
ty cycle is n ot correct.
Repair: There is a problem in the wiring between
theECMandth
e connector for the left rail or the
connector for the right rail. Repair the connectors
and/or wiring between the ECM and the connector
for the righ
t rail or the connector for the left rail.
STOP.
i02413610
Sensor Supply
SMCS Code: 5574-038
System Oper
ation Description:
Use this procedure to troubleshoot the electrical
system if a p
roblem is suspected with a sensor
supply or if any one of the diagnostic codes in Table
39 is active or easily repeated.