C175-16 Locomotive Engine Caterpillar

Fuel Control - Test

Usage:

Use this procedure to troubleshoot the electrical system if a problem is suspected with the fuel control valve. Also, use this procedure if one of the diagnostic codes in Table 1 is active.

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Table 1
J1939 Code and Description	CDL Code and Description	Comment
1076-7 Engine Fuel Injection Pump Fuel Control Valve : Not Responding Properly	18-7 Fuel Control Valve : Not Responding Properly	The commanded Fuel Control Valve (FCV) position does not match the actual FCV position.
1076-8 Engine Fuel Injection Pump Fuel Control Valve : Abnormal Frequency, Pulse Width, or Period	18-8 Fuel Control Valve : Abnormal Frequency, Pulse Width, or Period	The PWM signal between the Fuel Control Valve (FCV) and the ECM has been lost.
1076-11 Engine Fuel Injection Pump Fuel Control Valve : Other Failure Mode	18-11 Fuel Control Valve : Other Failure Mode	A failed Fuel Control Valve (FCV) has been detected.
1076-12 Engine Fuel Injection Pump Fuel Control Valve : Failure	18-12 Fuel Control Valve : Failure	A failed Fuel Control Valve (FCV) has been detected.
3597-6 ECU Power Output Supply Voltage #1 : Current Above Normal	1028-6 Power Supply Control 1 : Current Above Normal	A failed power supply to the fuel control valve has been detected.

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Illustration 1	g06090796
All the electrical connectors may not be shown. Refer to the schematic for more detail.

Note: Refer to Troubleshooting, "Electrical Connectors" for an Illustration of the ECM and Connectors.

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Table 2
Troubleshooting Test Steps	Values	Results
1. Check for Codes A. Apply electrical power to the engine. B. Connect Cat® Electronic Technician (ET) to the service tool connector. C. Determine if a code is active or logged.	Codes	Result: An 18–7, 18–11, 18–12, 1076–7, 1076–11 or 1076-12 code is present. Repair: A failed fuel control valve (FCV) has been detected. Release the pressure in the high-pressure rail by loosening the end plug on one of the last two fuel accumulators. Refer to Testing and Adjusting, "Fuel Rail Pressure - Release" for instructions on how to release the pressurized fuel. Verify the "Fuel Rail Pressure" reading in ET is 0 ± 8 MPa (0 ± 1160 psi) prior to servicing the fuel system. Replace the fuel control valve (FCV). Proceed to Test Step 9. Result: An 18–8 or 1076-8 code is present. Proceed to Test Step 2. Result: A 1028–6 or 3597-6 code is active. Proceed to Test Step 5.
2. Check the Wiring Between the ECM and the Fuel Control Valve (FCV) for an Open Circuit A. Remove electrical power from the engine. B. Disconnect the fuel control valve from the wiring harness. C. Disconnect the J-1 ECM connector from the engine ECM. D. Measure the resistance between pin 38 on the J-1 ECM connector and pin 11 on the FCV connector.	Open Circuit	Results: Less than 10 ohms of resistance between pin 38 on the J-1 engine ECM connector and pin 11 on the FCV connector. Proceed to Test Step 3. Results: More than 10 ohms of resistance between pin 38 on the J-1 engine ECM connector and pin 11 on the FCV connector. An open circuit in the wiring harness has been detected. Repair: Repair or replace the wiring harness as necessary. Proceed to Test Step 9.
3. Check the Wiring Between the ECM and the Fuel Control Valve (FCV) for a Short Circuit to Ground A. Remove electrical power from the engine. B. Disconnect the fuel control valve from the wiring harness. C. Disconnect the J-1 ECM connector from the engine ECM. D. Measure the resistance between pin 11 on the FCV connector and a known good ground.	Short Circuit	Results: There was more than 100 K ohms of resistance between pin 11 on the FCV connector and a known good ground. Proceed to Test Step 4. Results: There was less than 100 K ohms of resistance between pin 11 on the FCV connector and a known good ground. A short circuit to ground in the wiring harness has been detected. Repair: Repair or replace the wiring harness as necessary. Proceed to Test Step 9.
4. Check the Wiring Between the ECM and the Fuel Control Valve (FCV) for a Pin to Pin Short Circuit A. Remove electrical power from the engine. B. Disconnect the fuel control valve from the wiring harness. C. Disconnect the J–1 ECM connector from the engine ECM. D. Measure the resistance between pin 38 on the J–1 ECM connector and all other pins in the J–1 ECM connector.	Short Circuit	Results: More than 100 K ohms of resistance between pin 38 on the J-1 ECM connector and all other pins in the J-1ECM connector. Proceed to Test Step 5. Results: Less than 100 K ohms of resistance between pin 38 on the J–1 ECM connector and all other pins in the J–1 ECM connector. A pin to pin short circuit in the wiring harness has been detected. Repair: Repair or replace the wiring harness as necessary. Proceed to Test Step 9.
5. Check for System Voltage at the fuel control valve connector A. Remove electrical power from the engine. B. Disconnect the fuel control valve from the wiring harness. C. Apply electrical power to the engine. D. Measure the voltage between pin 8 on the fuel control valve connector and a known good ground.	System Voltage	Result: System voltage was present at pin 8. The system is working properly. Verify that the repair resolved the issue. Return to service. Result: System voltage was NOT present at pin 8. Proceed to test Step 6.
6. Check for an Open Circuit in the Fuel Control Valve Wiring A. Remove electrical power from the engine. B. Disconnect the fuel control valve from the wiring harness. C. Disconnect the J–1 connector from the ECM. D. Measure the resistance between pin 8 on the fuel control valve wiring harness connector and pin 48 on the J-1 connector.	Open Circuit	Result: Less than 10 ohms of resistance between the pins. Proceed to Test Step 7. Result: More than 10 ohms of resistance between the pins. An open circuit has been detected. Repair: Repair or replace the wiring harness as necessary. Verify that the repair resolved the issue. Return to service.
7. Check for a Short Circuit in the Fuel Control Valve Wiring A. Remove electrical power from the engine. B. Disconnect the fuel control valve from the wiring harness. C. Disconnect the J-1 connector from the ECM. D. Measure the resistance between pin 8 on the fuel control valve wiring harness connector and a known good ground.	Short Circuit	Result: More than 100 K ohms of resistance between pin 8 and a known good ground. Proceed to Test Step 8. Result: Less than 100 K ohms of resistance between pin 8 and a known good ground. A short circuit has been detected. Repair: Repair or replace the wiring harness as necessary. Verify that the repair resolved the issue. Return to service.
8. Check for a Pin to Pin Short Circuit in the Fuel Control Valve Wiring A. Remove electrical power from the engine. B. Disconnect the fuel control valve from the wiring harness. C. Disconnect the J-1 connector from the ECM. D. Measure the resistance between pin 48 on the J-1 ECM connector and all other pins on the connector.	Short Circuit	Result: More than 100 K ohms of resistance between pin 48 on the J-1 connector and all other pins on the J-1 ECM harness connector. Reconnect the fuel control valve wiring harness and the J-1 connector to the engine ECM. Proceed to Test Step 9. Result: Less than 100 K ohms of resistance between pin 48 on the J-1 connector and all other pins on the J-1 ECM harness connector. A pin to pin short circuit has been detected. Repair: Repair or replace the wiring harness as necessary. Verify that the repair resolved the issue. Return to service.
9. Check for Diagnostic Codes A. Start the engine. B. Connect Cat ET to the service tool connector. C. Determine if a code is active or logged.	Diagnostic Codes	Results: No codes are present. Return to service.

If the procedure did not correct the issue, contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).