C3.4B Engines Caterpillar


Sensor (Data Link Type) - Test - Ammonia Sensor

Usage:

CCS7 4B2
This procedure covers the following codes:

Table 1
Diagnostic Trouble Codes for the Ammonia Sensor 
J1939 Code  Description  Notes 
4377-2  Aftertreatment 1 Outlet NH3 : Erratic, Intermittent, or Incorrect  The Electronic Control Module (ECM) detects an open or short circuit error message for one of the ammonia sensor measuring cell lines for at least 12 seconds.
The warning lamp will flash. The engine will be derated. 
4377-4  Aftertreatment 1 Outlet NH3 : Voltage Below Normal  The ECM detects an open circuit error message for the signal ground line of the ammonia sensor for at least 2 seconds.
The warning lamp will flash. The engine will be derated. 
4377-7  Aftertreatment 1 Outlet NH3 : Not Responding Properly  The ECM detects an open or short circuit error message for the temperature cell input line or the trim resistor line input of the ammonia sensor for at least 2 seconds.
The warning lamp will flash. The engine will be derated. 
4377-12  Aftertreatment 1 Outlet NH3 : Failure  The ECM detects an invalid signal from the ammonia sensor for at least 2 seconds.
The warning lamp will flash. The engine will be derated. 
4377-19  Aftertreatment 1 Outlet NH3 : Data Error  The ECM detects a loss of signal from the ammonia sensor for at least 0.5 seconds.
The warning lamp will come on. 
4377-20  Aftertreatment 1 Outlet NH3 : Data Drifted High  The ECM detects that the sensor signal has drifted outside of the acceptable values for at least 20 seconds.
The warning lamp will flash. The engine will be derated. 
4383-5  Aftertreatment 1 Outlet NH3 Gas Sensor Heater Control : Current Below Normal  The ECM detects a low current condition on the ammonia sensor heater circuit for at least 2 seconds.
The warning lamp will flash. The engine will be derated. 
4383-6  Aftertreatment 1 Outlet NH3 Gas Sensor Heater Control : Current Above Normal  The ECM detects a high current condition on the ammonia sensor heater circuit for at least 2 seconds.
The warning lamp will flash. The engine will be derated. 
4383-7  Aftertreatment 1 Outlet NH3 Gas Sensor Heater Control : Not Responding Properly  The ECM detects an error message from the ammonia sensor for the sensor heater circuit at least 15 seconds.
The warning lamp will flash. The engine will be derated. 


Illustration 1g03731618
Schematic diagram for the ammonia sensor
Not all connectors are shown. Refer to the Electrical Schematic for the application.


Illustration 2g03729557
View of the pin locations on the P1 connector for the ammonia sensor.
(23) J1939 CAN 2 +
(45) J1939 CAN 2 -

Table 2
Troubleshooting Test Steps  Values  Results 

1. Inspect Electrical Connectors and Wiring

A. Check the fuses.

B. Thoroughly inspect the connectors for the ammonia sensor. Refer to Troubleshooting, "Electrical Connector - Inspect" for details.

C. Thoroughly inspect the P1/J1 ECM connector . Refer to Troubleshooting, "Electrical Connector - Inspect" for details.

D. Perform a 30 N (6.7 lb) pull test on each of the wires that are associated with the ammonia sensor.
 

Damaged wire or connector 

Result: A damaged wire or damaged connector was found. A fuse is blown.

Repair: Repair the damaged wire or the damaged connector. Replace any blown fuses.
Use the electronic service tool to clear all logged diagnostic codes. Verify that the repair eliminates the fault.

Result: All connectors, pins, and sockets are correctly connected and/or inserted and the harness is free of corrosion, of abrasion or of pinch points. The fuses are OK.

Proceed to Test Step 2.
 

2. Check for 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.

D. Monitor the electronic service tool for active diagnostic codes and/or logged diagnostic codes.
 

Diagnostic codes 

Result: A diagnostic code other than those listed in Table 1 is active or recently logged.

Repair: Troubleshoot the other diagnostic codes before returning to this procedure. Refer to Troubleshooting, "Diagnostic Trouble Codes".

Result: One of the diagnostic listed in Table 1 is active or recently logged.

Proceed to Test Step 3.

Result: None of the diagnostic codes listed in Table 1 are active or recently logged.

Repair: The fault may be intermittent. Refer to Troubleshooting, "Electrical Connector - Inspect" in order to identify intermittent faults.
 

3. Inspect the Exhaust System for Defects

A. Thoroughly inspect the exhaust system for leaks and/or restrictions. Refer to Systems Operation, Testing and Adjusting, "Air Inlet and Exhaust System - Inspect".
 

Exhaust leaks 

Result: There is a leak in the exhaust system.

Repair: Make any necessary repairs.
Run the engine. Use the electronic service tool in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault.

Result: The exhaust system is restricted with white deposits.

Repair: Refer to Troubleshooting, "Exhaust System Contains DEF Deposits"

Result: The exhaust system is OK.

Proceed to Test Step 4.
 

4. Inspect the Ammonia Sensor

A. Inspect the ammonia sensor for damage.

B. Check that the ammonia sensor is mounted in the correct position.

C. Ensure that the ammonia sensor is mounted securely
 

Ammonia sensor 

Result: Fault found with the ammonia sensor.

Repair: Make any necessary repairs. If necessary, replace a damaged ammonia sensor. Refer to Disassembly and Assembly for the correct procedure.
Run the engine. Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault.

Result: The ammonia sensor is mounted securely and not damaged.

Proceed to Test Step 5.
 

5. Check the Power Supply at the Ammonia Sensor

A. Turn the keyswitch to the OFF position.

B. Disconnect the connector for the ammonia sensor.

C. Turn the keyswitch to the ON position.

D. Use a multimeter to measure the voltage between terminal 1 and terminal 4 on the harness connector for the ammonia sensor.

E. Turn the keyswitch to the OFF position.
 

10 V to 14 V 

Result: The measured voltage is not within the expected range.

Proceed to Test Step 6.

Result: The measured voltage is within the expected range.

Proceed to Test Step 7.
 

6. Check the Power Supply and Ground Wiring for the Ammonia Sensor

A. Turn the keyswitch to the OFF position.

B. Disconnect the connector for the ammonia sensor. Disconnect the auxiliary main relay.

C. Use a multimeter to measure the resistance between the following points:

· Terminal 1 on the harness connector for the ammonia sensor and terminal 87 on the harness connector for the auxiliary main relay.
· Terminal 4 on the harness connector for the ammonia sensor and a suitable ground.
 

Less than 5 Ohms 

Result: At least one of the resistance measurements is greater than 5 Ohms.

Repair: Check the fuse.
If the fuse is OK, the fault is in the power supply or ground wiring for the ammonia sensor.
Replace the faulty wiring.
Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault.

Result: Both resistance measurements are less than 5 Ohms.

Repair: Install a replacement auxiliary main relay.
Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault. 

7. Check the CAN Data Link

A. Check the CAN data link for faults. Refer to Troubleshooting, "CAN Data Link - Test".
 

CAN Data Link 

Result: A fault was found on the CAN data link.

Repair: Make any necessary repairs.
Run the engine. Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault.

Result: The CAN data link is OK.

Repair: Install a replacement ammonia sensor. Refer to Disassembly and Assembly for the correct procedure.
 
If the procedure did not correct the fault, contact the Dealer Solution Network (DSN). 

Caterpillar Information System:

352F Excavator Plate Locations and Film Locations
DE Series Generator Set With Cat C7.1 Engine Refill Capacities and Recommendations
DE Series Generator Set With Cat C7.1 Engine Model View Illustrations
DE Series Generator Set With Cat C7.1 Engine Safety Messages
3500E EPA Tier 4 Final and IMO-II/III Switchable Marine Engines Air Shutoff - Test
Engine System Setup for Certified CG137-12 Generator Set Engines {1270, 1278} Engine System Setup for Certified CG137-12 Generator Set Engines {1270, 1278}
2014/10/03 Cat® Reman Announces Additional C7 Engine Options for Certain Thomas Built Bus Applications {1000, 1201}
DE Series Generator Set With Cat C7.1 Engine Product Description
G3512H and G3516H Generator Set Engines Air Inlet Manifold - Remove and Install
Radiator for C4.4 Marine Generator Set{1353} Radiator for C4.4 Marine Generator Set{1353}
C3.4B Engines Relay - Test - Start Relay
XQ400 Power Module Gas Pressure Regulator - Test
C4.4 Engines for Caterpillar Built Machines Nitrogen Oxide Sensor - Remove and Install - Nitrogen Oxide Sensor Positioned in Original Equipment Manufacture (OEM) Exhaust Tube Assembly
794 AC Off-Highway Truck Machine Systems Service and Parking Brake (Front) - Remove and Install
20 GPM Portable Fuel Filtration System {0374, 0599, 0706, 1250, 1256, 1261} 20 GPM Portable Fuel Filtration System {0374, 0599, 0706, 1250, 1256, 1261}
G3520H Generator Set Engine Water Temperature Regulators - Remove and Install
TA22-4WD Agricultural Transmission Maintenance Interval Schedule
2014/10/03 Cat® Reman Now Offers Upgrade to New Cylinder Heads for Certain Engines {1100}
C7 and C9 Industrial Engines ECM - Replace
794 AC Off-Highway Truck Machine Systems Service and Parking Brake (Front) - Disassemble
794 AC Off-Highway Truck Machine Systems Service and Parking Brake (Front) - Assemble
C7 and C9 Industrial Engines Oil Pressure Is Low
C7 and C9 Industrial Engines Oil Temperature Is High
C7 and C9 Industrial Engines Injection Actuation Pressure Control Valve - Test
Back to top
The names Caterpillar, John Deere, JD, JCB, Hyundai or any other original equipment manufacturers are registered trademarks of the respective original equipment manufacturers. All names, descriptions, numbers and symbols are used for reference purposes only.
CH-Part.com is in no way associated with any of the manufacturers we have listed. All manufacturer's names and descriptions are for reference only.