System Operation Description:
The ARD nozzle can become plugged with carbon or with debris. The engine is equipped with a system that cleans the nozzle. The Engine Control Module (ECM) periodically tests the condition of the nozzle. The ARD combustion head contains an electric heating element. The heating element operates periodically in order to clean the nozzle.
This test is to verify the correct operation of the ARD nozzle heater electrical circuit.
| Troubleshooting Test Steps | Values | Results |
|---|---|---|
| 1. Check the Device that is Used for Circuit ProtectionReferences will be made to system voltage. The system voltage of a typical 12V system is usually 12V to 16V.
The system voltage of a typical 24V system is usually 24V to 28V. A. Measure the voltage on the supply side of the device that is used for circuit protection. B. Measure the voltage on the load side of the device that is used for circuit protection. |
12V to 16V on a 12V system or 24V to 28V on a 24V system |
Result: The voltage is equal to system voltage on both sides of the device that is used for circuit protection.Proceed to Test Step 4.
Result: The voltage is not equal to system voltage on the supply side of the circuit protection device. The problem is in the wiring to the battery. Repair the wiring. Proceed to Test Step 11. Result: The voltage is not equal to system voltage on the load side of the circuit protection device. Proceed to Test Step 2. |
| Troubleshooting Test Steps | Values | Results |
|---|---|---|
| 2. Reset the Protection DeviceA. Reset the protection device or replace the circuit protection device.
B. Start the engine. C. Perform the ARD nozzle heater circuit test in Cat ET. |
Circuit protection device or circuit | Result: The circuit protection trips.Proceed to Test Step 3.
Result: The circuit protection does not trip. There is a problem in the wiring circuit for the ARD heater. Proceed to Test Step 4. |
| 3. Check the ARD HeadA. Turn the key to the OFF position
B. Disconnect the connector to the heater at the ARD head. C. Reset the protection device or replace the circuit protection device. D. Start the engine. E. Perform the ARD nozzle heater circuit test in Cat ET. |
ARD head | Result: The circuit protection trips.There is a problem in the wiring circuit for the ARD heater. Proceed to Test Step 4.
Result: The circuit protection does not trip. Replace the ARD head and Proceed to Test Step 11. |
| 4. Inspect the WiringA. Carefully inspect the wiring for the system. Look for the following problems:
1. Loose connectors or damaged connectors |
Damaged wires or connectors | Result: The wiring was not OK.Replace the wiring or repair the wiring. Proceed to Test Step 11.
Result: The wiring was OK. Proceed to Test Step 5. |
Illustration 2 g02226955
CEM (typical)
(1) Relay for the ARD nozzle heater
| Troubleshooting Test Steps | Values | Results |
|---|---|---|
| 5. Check for System Voltage at the ARD Heater RelayA. Turn the keyswitch to the “ON” position.
B. Measure the voltage between terminal 3 and terminal 4 on the ARD heater relay. |
Equal to system voltage | Result: The voltage between terminal 3 and terminal 4 on the ARD heater relay is equal to system voltage.Proceed to Test Step 6.
Result: The voltage between terminal 3 and terminal 4 on the ARD heater relay is not equal to system voltage. The problem is between terminal 3 on the ARD heater relay and the circuit protection device or the problem is that terminal 4 does not have a good ground source. Repair the problem. Proceed to Test Step 11. |
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Illustration 3 g02326154
CEM (typical)
(2) Two-pin ARD heater wire connector
| Troubleshooting Test Steps | Values | Results |
|---|---|---|
| 6. Check for System Voltage at the Two-Pin ARD Heater Wire ConnectorA. Start the engine.
B. Establish communication between Cat ET and the ECM . C. Perform the “ARD Nozzle Heater Circuit Test”. D. Measure the voltage between battery ground and terminal 1 on the two-pin ARD heater wire connector. |
Equal to system voltage | Result: The voltage between battery ground and terminal 1 is equal to system voltage.Proceed to Test Step 10.
Result: The voltage between battery ground and terminal 1 is not system voltage. Proceed to Test Step 7. |
| 7. Check for Output Voltage from the ARD Heater RelayA. Start the engine.
B. Establish communication between Cat ET and the ECM . C. Perform the “ARD Nozzle Heater Circuit Test”. D. Measure the voltage between terminal 2 on the ARD heater relay and battery ground. Power to the ECM must be OFF before reconnecting the relay. |
Equal to system voltage | Result: The voltage between terminal 2 and battery ground is equal to system voltage.The problem is between terminal 2 on the ARD heater relay and the two pin ARD heater wire connector. Repair or replace the damaged wire. Proceed to Test Step 11.
Result: The voltage between terminal 2 and battery ground is not equal to system voltage. Proceed to Test Step 8. |
| 8. Check for System Voltage at the ARD Heater RelayA. Start the engine.
B. Establish communication between Cat ET and the ECM . Refer to Troubleshooting, “Electronic Service Tools”, if necessary. C. Perform the “ARD Nozzle Heater Circuit Test”. D. Measure the voltage between battery ground and terminal 1 on the ARD heater relay. Power to the ECM must be OFF before reconnecting the relay. |
System voltage | Result: The voltage between terminal 1 on the ARD heater relay and battery ground is equal to system voltage.The ARD heater relay is not operating properly. Replace the ARD heater relay. Proceed to Test Step 11.
Result: The voltage between terminal 1 on the ARD heater relay and battery ground is not equal to system voltage. Proceed to Test Step 9. |
| 9. Check for System Voltage at the ECMA. Start the engine.
B. Establish communication between Cat ET and the ECM . Refer to Troubleshooting, “Electronic Service Tools”, if necessary. C. Perform the “ARD Nozzle Heater Circuit Test”. D. Measure the voltage between battery ground and terminal 45 on the ECM. Power to the ECM must be OFF before reconnecting the relay. |
System voltage | Result: The voltage between ECM terminal 45 and battery ground is equal to system voltage.Repair or replace the wiring between the ECM and the ARD heater relay.
Proceed to Test Step 11. Result: The voltage between ECM terminal 45 and battery ground is not equal to system voltage. The ECM is not working properly, replace the ECM. Proceed to Test Step 11. |
Illustration 4 g02360956
ARD combustion head
(3) Port for the heated nozzle
Illustration 5 g02326213
(4) Connector for the heated nozzle
(5) Measurement location on the wire
| Troubleshooting Test Steps | Values | Results |
|---|---|---|
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10. Check for Voltage at the ARD Head
A. Remove the retaining clip from the ARD nozzle heater. B. Disconnect the wire to the ARD nozzle heater. C. Start the engine. D. Establish communication between Cat ET and the ECM . E. Perform the “ARD Nozzle Heater Circuit Test”. F. Check for voltage at the connector for the ARD nozzle heater. Refer to illustration 5 for the proper measurement location. Power to the ECM must be OFF before reconnecting the relay. System voltage is typically ± 5 VDC of battery voltage. |
Equal to system voltage |
Result: The voltage is equal to system voltage.
Replace the ARD head. Inspect the coolant supply and return lines to the ARD head for restrictions or blockage. Proceed to Test Step 11. Result: The voltage is not equal to system voltage. Repair the wiring or replace the wiring between the two pin connector and the ARD nozzle heater. Proceed to Test Step 11. |
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11. Check the Current Flow to the Heating Element in the ARD Combustion Head
Start the engine. Check the current flow to the heater. Refer to Systems Operation/Testing and Adjusting, “ARD Nozzle Heater (Current)- Test” for the correct procedure. |
7.0 A and 14 A for a 12 V system or 3.5 A and 7 A for a 24 V system |
Result: The current flow is between 7.0 A and 14 A for a 12 V system. Or, the current flow is between 3.5 A and 7 A for a 24 V system. The current flow is OK. Proceed to Test Step 12. Result: The current flow is not between 7.0 A and 14 A for a 12 V system. Or, the current flow is not between 3.5 A and 7 A for a 24 V system. Repeat the procedure starting with Test Step 1 or Contact your Cat dealer Technical Communicator (TC). |
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12. Perform a ARD Fuel Nozzle Heat Cycle
A. Start the engine. The ECM must have an engine speed signal to initiate the ARD nozzle heater cycle. B. Activate the “Aftertreatment #1 Fuel Injector #1 Heater Override”. Refer to Troubleshooting, “Cat ET Service Features” for information about this override. The cycle for the ARD nozzle heater will cycle the nozzle ON and OFF for an hour in order to clean the nozzle. |
Successful nozzle cleaning |
Result: The ARD nozzle heater cycle completed successfully.
Proceed to Test Step 13. |
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13. Perform a Manual DPF Regeneration
This test must be performed through Cat ET. The Cat ET service tool enhances the diagnostics during the service test. Cat ET will display a “Waiting On Requirements” window. The ECM will automatically elevate the engine speed. The duration of the regeneration depends on the soot load in the diesel particulate filter. The ECM will automatically return the engine speed to low idle after the regeneration is complete. The ECM tests the nozzles for plugging after the regeneration is complete. A “Aftertreatment Fuel Injector #1 : Not Responding Properly” code will become active if the nozzles are plugged. |
Successful Manual DPF Regeneration |
Result: The service regeneration completes successfully.
Return the engine to service. |
Test Step 1.
Complete the procedure in the order in which the steps are listed.
Results:
- The procedure corrected the issue. – STOP
- The procedure did not correct the issue. –Repair: Contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).
STOP
