DTC 522810-4
Alternator Charge Excitation Signal OORL
Alternator Excitation Signal Is Below Allowable Threshold
POSSIBLE CAUSE
A. EXCITATION SIGNAL SHORTED TO GROUND
B. EXCITATION SIGNAL OPEN CIRCUIT
C. PDM FUNCTIONAL FAILURE
D. FUNCTIONAL FAILURE IN CONTROLLER
NOTE
Please refer to the end of this procedure for supporting diagrams.
COMPONENT OPERATIONAL CHECK
PROCEDURE OR ACTION:
NOTE: This fault can be caused by a missing resistor in the PDM. Open the PDM and verify that the 68? resistor
is correctly installed. (See PDM Component Locator Diagram.)
1. Turn power to OFF for no less than 30 seconds, and then to ON to clear displayed DTC.
Does reported DTC reoccur?
YES: Go to Step 2.
NO: Problem not verified. Resume operation.
2. Conduct a quick visual inspection of all connectors/wiring associated with the displayed fault code.
Are any faults detected/observed?
YES: Repair/replace connector or wiring associated with faults found. See Electrical System 2200SRM1142.
NO: Go to Cause A.
CAUSE A - EXCITATION SIGNAL SHORTED TO GROUND
PROCEDURE OR ACTION:
1. Ensure truck power is OFF.
2. Open the cover on the PDM.
3. Remove the 68? resistor.
4. Disconnect the indicated connector from the VSM.
5. On the DMM, change the scale to ohms. Verify DMM zero reading.
6. At the VSM harness connector, measure resistance between the excitation signal pin and the negative terminal
of the battery.
Is the resistance less than 0.5 ohms?
YES: The excitation signal is shorted to ground. Go to Step 7.
NO: Go to Cause B.
7. Disconnect the CPS 15 connector from the PDM.
8. Repeat measurement from Step 6.
Is the resistance less than 0.5 ohms?
YES: The excitation signal is shorted to ground in the harness. Locate and repair/replace the shorted wire/
connection. See Wire Harness Repair 2200SRM1128.
NO: The excitation signal is shorted to ground in the PDM. Replace the PDM. See Electrical System
2200SRM1142.
Diagnostic Trouble Codes Electrical System
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DTC 522810-4 (Cont)
Alternator Charge Excitation Signal OORL
CAUSE B - EXCITATION SIGNAL OPEN CIRCUIT
PROCEDURE OR ACTION:
1. Ensure truck power is OFF.
2. On the DMM, select the ohms scale. Verify DMM zero reading.
3. With the indicated connectors at the VSM and PDM disconnected, measure resistance of the excitation signal
wire between the indicated pins.
Is the resistance less than 0.5 ohms?
YES: Go to Cause C.
NO: The excitation signal wire is open. Locate and repair/replace open wire/connection. See Wire Harness
Repair 2200SRM1128.
CAUSE C - PDM FUNCTIONAL FAILURE
PROCEDURE OR ACTION:
1. Remove the 68? resistor from the PDM.
2. Measure the resistance of the resistor.
Is the resistance approximately 68??
YES: Go to Step 3.
NO: Replace resistor. See Electrical System 2200SRM1142. Replace/reconnect all components and repeat
Component Operational Check.
3. Reinstall the resistor and reconnect the indicated connectors to the PDM.
4. At the VSM harness connector, measure the resistance between pins 12 and 9 of CPS 1.
Is the resistance approximately 68??
YES: Go to Cause D.
NO: Replace the PDM. See Electrical System 2200SRM1142. Reinstall/reconnect all components and repeat
Component Operational Check.
CAUSE D - FUNCTIONAL FAILURE IN CONTROLLER
PROCEDURE OR ACTION:
1. Ensure all previous procedures have been completed.
2. Ensure truck power is OFF.
3. Ensure that all connections to the controller are completely inserted.
4. Ensure truck power is OFF for no less than 30 seconds, and then to ON to clear displayed DTC.
Does reported DTC reoccur?
YES: Go to Step 5.
NO: Problem corrected. Resume operation.
5. At the DSC, press ENTER to access Main Menu.
6. Scroll to VIEW VERSIONS, press ENTER.
7. Scroll to TRUCK SERIAL NUMBER, press ENTER.
8. View the TRUCK SERIAL NUMBER on the display.
Does the truck serial number on display match serial number on truck nameplate (VSM Only)?
YES: Go to Step 9.
NO: Controller has been substituted from another truck. Replace VSM with VSM that has the correct truck
serial number or obtain new VSM with correct Serial number/ CDF. See Electrical System 2200SRM1142