Perkins 1104E Series Troubleshooting Manual page 167

RENR2696-01
Test Step 3. Measure the Sensor
Resistance Through the Wiring Harness
Illustration 79
A. Turn the keyswitch to the OFF position.
B. Remove the P1 ECM connector.
C. Use a multimeter to measure the resistance of the
sensor from 41 terminal to 49 terminal.
D. Wiggle the cables that are associated with the
engine speed/timing sensor while the resistance
is measured in order to check for an intermittent
open or short circuit.
Refer to Illustration 79.
E. The resistance between the terminals should be
from 75 to 230 ohms.
Expected Result:
The readings agree with the values that are listed
above.
Results:
•
OK – Neither a short circuit nor an open circuit is
indicated. Proceed to Test Step 5.
•
Not OK – The resistance is not within the
acceptable range when the circuit resistance is
measured through the engine harness. Proceed
to Test Step 4.
Test Step 4. Measure the Resistance of
the Sensor
A. Turn the keyswitch to the OFF position.
B. Check the harness and the wiring for abrasion and
pinch points from the sensor back to the ECM.
C. Disconnect P401 engine speed/timing sensor
connector.
D. Thoroughly inspect the J401/P401 engine
speed/timing sensor connector. Refer to
Troubleshooting, "Electrical Connectors - Inspect".
E. The resistance between the terminals should be
from 75 to 230 ohms.
Expected Result:
The readings agree with the values that are listed
above.
Results:
•
OK – The sensor resistance is within tolerance.
Repair: There is a fault in the cable between the
P1 ECM connector and the P401 connector.
Repair the faulty cable or replace the faulty cable.
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Troubleshooting Section
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