Table 227
Troubleshooting Test Steps
Values Results
1. Inspect Electrical Connectors and Wiring
A. Thoroughly inspect the terminal connections on the P1/J1
ECM connector and the PWM throttle position sensors.
Refer to Troubleshooting, “Electrical Connector - Inspect”.
B. Perform a 45 N (10 lb) pull test on each of the wires in the
ECM connector and the PWM throttle position sensor
connector.
C. Check the screw for the ECM connector for the correct tor-
que of 6 N·m (53 lb in).
D. Check the harness for corrosion, abrasion, and pinch points
from the PWM throttle position sensor to the ECM.
Loose connection or
damaged wire
Result: There is a fault in a connector or the wiring.
Repair: Repair any faulty connectors or replace the wir-
ing harness. Ensure that all of the seals are properly in
place and ensure that the connectors are correctly
coupled.
Use the electronic service tool to clear all logged diag-
nostic codes and verify that the repair eliminates the
fault.
Result: All connectors, pins, and sockets are correctly
coupled and/or inserted. The harness is free of corro-
sion, abrasion, and pinch points.
Proceed to Test Step 2.
2. Check for Active Diagnostic Codes
A. Turn the keyswitch to the OFF position.
B. Connect the electronic service tool to the diagnostic
connector.
C. Turn the keyswitch to the ON position. Wait at least 10 sec-
onds for activation of the diagnostic codes.
D. Verify if any of the diagnostic codes that are listed in Table
226 are active.
Note: When the ECM calibrates new duty cycle values for the
low and the high idle throttle position, the ECM assumes the
initial lower position for the duty cycle at low idle and the initial
upper position for the duty cycle at high idle. The initial lower
position and the initial upper position can be obtained by ac-
cessing the following screens on the electronic service tool:
· Service
· Throttle Configuration
· “Throttle# 1”
As a result, the throttle position status may reach 100 percent
well before the throttle pedal is fully depressed. This situation
is normal. Cycle the throttle to the high idle position several
times for the ECM to adjust the calibration automatically. Dur-
ing normal operation, more movement of the throttle can be
required for the throttle position status to increase above 3
percent. The status may reach the 100 percent value prior to
the limit of the high idle position. This process is done to en-
sure that the throttle reaches these two critical points for en-
gine operation.
E. Turn the keyswitch to the OFF position.
Diagnostic codes Result: At least one of the diagnostic codes listed in Ta-
ble 226 is active.
Proceed to Test Step 4.
Result: None of the preceding diagnostic codes are ac-
tive or recently logged - There may be an intermittent
fault.
Repair: Refer to Troubleshooting, “Electrical Connector
- Inspect” in order to identify intermittent faults.
If the fault is still present, proceed to Test Step 3.
(continued)
428 UENR4469-36
Circuit Tests
Copyright of Perkins Engine Company Limited. NOT FOR REPRINTING OR RESALE
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