Perkins NJ Series Troubleshooting Manual page 155

SENR9982-01
• Not OK
Repair: Repair the connectors or the harness
and/or replace the connectors or the harness.
Ensure that all of the seals are correctly in place
and ensure that the connectors are completely
coupled.
Use the electronic service tool in order to clear all
logged diagnostic codes and then verify that the
repair eliminates the fault.
STOP.
Test Step 3. Verify that the Diagnostic
Code is Still Active.
A. Turn the keyswitch to the ON position. Wait at
least 10 seconds for activation of the diagnostic
codes.
B. Use the Perkins EST to check for active diagnostic
codes. Record all active diagnostic codes.
C. Determine if the fault is related to an open circuit
diagnostic code or a short circuit diagnostic code.
Expected Result:
Either a short circuit diagnostic code is active or an
open circuit diagnostic code is active.
Results:
•
OK - SHORT Circuit – A Voltage Above Normal
diagnostic code is active at this time. Proceed to
Test Step 4.
• OK - OPEN Circuit – A Voltage Below Normal
diagnostic code is active at this time. Proceed to
Test Step 5.
• Not OK – A short circuit diagnostic code is not
active. An open circuit diagnostic code is not
active. An intermittent fault may exist.
Repair: By using the Perkins EST, perform a
"Wiggle Test". If faults are indicated then go to the
appropriate procedure.
STOP.
Test Step 4. Disconnect The Sensor In
Order To Create An Open Circuit.
A. Turn the keyswitch to the OFF position.
B. Disconnect the sensor connector of the sensor
with the short circuit diagnostic code.
C. Turn the keyswitch to the ON position. Wait at
least 10 seconds for activation of the diagnostic
codes.
D. Use the Perkins EST to check the "Active
Diagnostic Code" screen. Check for a Voltage
Below Normal diagnostic code.
Expected Result:
A Voltage Below Normal diagnostic code for the
disconnected sensor is now active.
Results:
•
OK – A Voltage Above Normal diagnostic code
was active before disconnecting the sensor. An
Voltage Above Normal diagnostic code became
active after disconnecting the sensor. Proceed to
Test Step 6.
•
Not OK – There is a short circuit between the
sensor harness connector and the ECM. Leave the
sensor disconnected. Proceed to Test Step 8.
Test Step 5. Measure the Sensor Supply
Voltage.
A. Turn the keyswitch to the OFF position.
B. Disconnect the sensor from the engine harness.
C. Turn the keyswitch to the ON position.
D. Measure the voltage at the plug for the sensor
from the terminal 1 (pressure sensor supply) to
terminal 2 (sensor common).
Expected Result:
The DC voltage from terminal 1 to terminal 2
measures 4.84 to 5.16 VDC.
Results:
• OK – The sensor supply voltage is correct.
Proceed to Test Step 7.
• Not OK – The sensor supply voltage is out of the
nominal range. Continue testing the sensor supply
circuit.
Repair: Proceed to the following repair:
Troubleshooting, "5 Volt Sensor Supply Circuit -
Test"
STOP.
Test Step 6. Determine If The Short
Circuit Is In The Connector Or In The
Sensor.
A. Thoroughly inspect the connector for moisture.
B. Inspect the seals and reconnect the sensor.
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Troubleshooting Section