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Product: EXCAVATOR
Model: 320 GX EXCAVATOR YBM30464
Configuration: 320 GX Excavator SYW00001-UP (MACHINE) POWERED BY C4.4 Engine
Troubleshooting
C4.4 Engines
Media Number -UENR0662-49 Publication Date -01/06/2015 Date Updated -01/06/2021
i06556246
Electrical Power Supply - Test
SMCS - 1401-038
Use this procedure to troubleshoot the electrical system if a problem is suspected with the power to
the engines Electronic Control Module (ECM). Use this procedure if any of the diagnostic codes in
Table 1 are active or easily repeated.
Table 1
Diagnostic Trouble Codes for the Electrical Power Supply
J1939 CDL Code Description
Comments
Code Code (code descriptions may vary)
Electrical System Voltage : Voltage The ECM detects voltage that is
168-3 168-3
Above Normal above the acceptable value.
Electrical System Voltage : Voltage The ECM detects voltage that is
168-4 168-4
Below Normal below the acceptable value.
Aftertreatment 1 Intake NOx : Current The ECM detects current that is
3216-5 3002-5
Below Normal below the acceptable value
Aftertreatment 1 Intake NOx : Current The ECM detects current that is
3216-6 3002-6
Above Normal above the acceptable value
Aftertreatment 1 Outlet NOx : Current The ECM detects current that is
3226-5 3609-5
Below Normal below the acceptable value
Aftertreatment 1 Outlet NOx : Current The ECM detects current that is
3226-6 3609-6
Above Normal above the acceptable value
Aftertreatment #1 DEF Controller : The ECM detects voltage that is
3360-3 3820-3
Voltage Above Normal above the acceptable value.
Aftertreatment #1 DEF Controller : The ECM detects voltage that is
3360-4 3820-4
Voltage Below Normal below the acceptable value.
4380-2 4592-2 Aftertreatment 1 Outlet NH3 Gas The ECM detects that the power
Sensor Power In Range : Erratic, supply to the ammonia (NH3)
Intermittent, or Incorrect sensor is not stable.
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5758- 3621- Engine Exhaust NOx Level Sensor The ECM detects voltage that is
11 11 Power Supply: Other Failure Mode outside the acceptable value.
Aftertreatment #1 Outlet#1 NOx Level
5759- 3619- The ECM detects voltage that is
Sensor Power Supply: Other Failure
11 11 outside the acceptable value.
Mode
The engine ECM requires the keyswitch to be in the ON position to maintain communications with
the electronic service tool.
Illustration 1 g03813883
Schematic diagram for the engine electrical power supply circuit
Not all connectors are shown. Refer to the appropriate electrical schematic
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Illustration 2 g03813894
Schematic diagram for the DCU electrical power supply circuit
Not all connectors are shown. Refer to the appropriate electrical schematic
Illustration 3 g03813890
Schematic for the NOx sensor power supply circuit
Not all connectors are shown. Refer to the appropriate electrical schematic
Complete the procedure in the order in which the steps are listed.
Table 2
Troubleshooting Test Steps Value Results
1. Determine the Diagnostic Code Result: One of the diagnostic
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codes listed in Table 1 is active.
A. Establish communication between the Diagnostic
electronic service tool and the ECM . code Proceed to Test Step 2.
Refer to Troubleshooting, "Electronic
Service Tools", if necessary. Result: The electronic service tool
will not communicate with the
B. Start the engine. Run the engine until ECM.
the engine is at normal operating
temperature. Repair: Refer to Troubleshooting,
"Electronic Service Tool Does Not
C. Observe the "Active Diagnostic" screen Communicate".
on the electronic service tool. Wait at least
30 seconds so that any codes may become
active.
2. Inspect Electrical Connectors and Result: A damaged wire or
Wiring damaged connector was found. A
blown fuse was found.
A. Ensure that the battery disconnect
switch is in the CLOSED position. Repair: Repair the damaged wire
or the damaged connector. Replace
B. Thoroughly inspect all connectors all blown fuses.
associated with the electrical power Use the electronic service tool to
supplies. clear all logged diagnostic codes.
Verify that the repair eliminates
C. Check all fuses. the fault.
Damaged wire
or connector.
D. Perform a 45 N (10 lb) pull test on each Result: The "System Operating
Blown fuse.
of the wires in the connectors associated Voltage Configuration" is
with the electrical power supplies. configured incorrectly.
E. Check all the wiring associated with the Repair: Program the parameter
electrical power supplies for abrasions and with the correct system voltage.
pinch points.
Result: A damaged wire or
F. Verify that the "System Operating damaged connector was not found.
Voltage Configuration" is correctly The fuses are OK.
configured in the Engine ECM
configuration parameters. Proceed to Test Step 3.
3. Load Test the Batteries Load test Result: The batteries pass the load
test.
A. Use a suitable battery load tester to test
the batteries. Refer to Systems Operation, Proceed to Test Step 4.
Testing and Adjusting, "Battery - Test" for
the correct procedure.
Result: The batteries do not pass
the load test.
Repair: Recharge or replace the
faulty batteries.
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Use the electronic service tool to
clear all logged diagnostic codes
and verify that the repair
eliminates the fault.
Result: The charging system is
OK.
Contact the Dealer Solutions
Network (DSN).
4. Check the Charging Circuit
Result: The charging system is not
OK.
A. Check the charging circuit. Refer to Charging circuit
Systems Operation, Testing and Adjusting,
Repair: There is a fault in the
"Charging System - Test".
charging system. Make the
necessary repairs.
Use the electronic service tool to
clear all logged diagnostic codes
and verify that the repair
eliminates the fault.
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