C175-16 Locomotive Engine Caterpillar

Injector Solenoid - Test

Usage:

Use this procedure to troubleshoot a problem with the injectors. Also, use this procedure if one of the following diagnostic codes is active or easily repeated.

Show/hide table

Table 1
J1939 Code and Description	CDL Code and Description	Comments
651-2 Engine Injector Cylinder #01 : Erratic, Intermittent, or Incorrect	1-2 Cylinder #1 Injector : Erratic, Intermittent, or Incorrect	The Electronic Control Module (ECM) has detected that an injector or injectors are not responding as desired.
651-5 Engine Injector Cylinder #01 : Current Below Normal	1-5 Cylinder #1 Injector : Current Below Normal	The ECM detects an open circuit.
651-6 Engine Injector Cylinder #01 : Current Above Normal	1-6 Cylinder #1 Injector : Current Above Normal	The ECM detects a short circuit.
651-7 Engine Injector Cylinder #01 : Not Responding Properly	1-7 Cylinder #1 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
651-20 Engine Injector Cylinder #01 : Data Drifted High	1-20 Cylinder #1 Injector : Data Drifted High	The ECM has detected under fueling injector.
651-21 Engine Injector Cylinder #01 : Data Drifted Low	1-21 Cylinder #1 Injector : Data Drifted Low	The ECM has detected over fueling injector.
652-2 Engine Injector Cylinder #02 : Erratic, Intermittent, or Incorrect	2-2 Cylinder #2 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
652-5 Engine Injector Cylinder #02 : Current Below Normal	2-5 Cylinder #2 Injector : Current Below Normal	The ECM detects an open circuit.
652-6 Engine Injector Cylinder #02 : Current Above Normal	2-6 Cylinder #2 Injector : Current Above Normal	The ECM detects a short circuit.
652-7 Engine Injector Cylinder #02 : Not Responding Properly	2-7 Cylinder #2 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
652-20 Engine Injector Cylinder #02 : Data Drifted High	2-20 Cylinder #2 Injector : Data Drifted High	The ECM has detected under fueling injector.
652-21 Engine Injector Cylinder #02 : Data Drifted Low	2-21 Cylinder #2 Injector : Data Drifted Low	The ECM has detected over fueling injector.
653-2 Engine Injector Cylinder #03 : Erratic, Intermittent, or Incorrect	3-2 Cylinder #3 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
653-5 Engine Injector Cylinder #03 : Current Below Normal	3-5 Cylinder #3 Injector : Current Below Normal	The ECM detects an open circuit.
653-6 Engine Injector Cylinder #03 : Current Above Normal	3-6 Cylinder #3 Injector : Current Above Normal	The ECM detects a short circuit.
653-7 Engine Injector Cylinder #03 : Not Responding Properly	3-7 Cylinder #3 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
653-20 Engine Injector Cylinder #03 : Data Drifted High	3-20 Cylinder #3 Injector : Data Drifted High	The ECM has detected under fueling injector.
653-21 Engine Injector Cylinder #03 : Data Drifted Low	3-21 Cylinder #3 Injector : Data Drifted Low	The ECM has detected over fueling injector.
654-2 Engine Injector Cylinder #04 : Erratic, Intermittent, or Incorrect	4-2 Cylinder #4 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
654-5 Engine Injector Cylinder #04 : Current Below Normal	4-5 Cylinder #4 Injector : Current Below Normal	The ECM detects open circuit.
654-6 Engine Injector Cylinder #04 : Current Above Normal	4-6 Cylinder #4 Injector : Current Above Normal	The ECM detects a short circuit.
654-7 Engine Injector Cylinder #04 : Not Responding Properly	4-7 Cylinder #4 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
654-20 Engine Injector Cylinder #04 : Data Drifted High	4-20 Cylinder #4 Injector : Data Drifted High	The ECM has detected under fueling injector.
654-21 Engine Injector Cylinder #04 : Data Drifted Low	4-21 Cylinder #4 Injector : Data Drifted Low	The ECM has detected over fueling injector.
655-2 Engine Injector Cylinder #05 : Erratic, Intermittent, or Incorrect	5-2 Cylinder #5 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
655-5 Engine Injector Cylinder #05 : Current Below Normal	5-5 Cylinder #5 Injector : Current Below Normal	The ECM detects an open circuit.
655-6 Engine Injector Cylinder #05 : Current Above Normal	5-6 Cylinder #5 Injector : Current Above Normal	The ECM detects a short circuit.
655-7 Engine Injector Cylinder #05 : Not Responding Properly	5-7 Cylinder #5 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
655-20 Engine Injector Cylinder #05 : Data Drifted High	5-20 Cylinder #5 Injector : Data Drifted High	The ECM has detected under fueling injector.
655-21 Engine Injector Cylinder #05 : Data Drifted Low	5-21 Cylinder #5 Injector : Data Drifted Low	The ECM has detected over fueling injector.
656-2 Engine Injector Cylinder #06 : Erratic, Intermittent, or Incorrect	6-2 Cylinder #6 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
656-5 Engine Injector Cylinder #06 : Current Below Normal	6-5 Cylinder #6 Injector : Current Below Normal	The ECM detects an open circuit.
656-6 Engine Injector Cylinder #06 : Current Above Normal	6-6 Cylinder #6 Injector : Current Above Normal	The ECM detects a short circuit.
656-7 Engine Injector Cylinder #06 : Not Responding Properly	6-7 Cylinder #6 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
656-20 Engine Injector Cylinder #06 : Data Drifted High	6-20 Cylinder #6 Injector : Data Drifted High	The ECM has detected under fueling injector.
656-21 Engine Injector Cylinder #06 : Data Drifted Low	6-21 Cylinder #6 Injector : Data Drifted Low	The ECM has detected over fueling injector.
657-2 Engine Injector Cylinder #07 : Erratic, Intermittent, or Incorrect	7-2 Cylinder #7 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
657-5 Engine Injector Cylinder #07 : Current Below Normal	7-5 Cylinder #7 Injector : Current Below Normal	The ECM detects an open circuit.
657-6 Engine Injector Cylinder #07 : Current Above Normal	7-6 Cylinder #7 Injector : Current Above Normal	The ECM detects a short circuit.
657-7 Engine Injector Cylinder #07 : Not Responding Properly	7-7 Cylinder #7 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
657-20 Engine Injector Cylinder #07 : Data Drifted High	7-20 Cylinder #7 Injector : Data Drifted High	The ECM has detected under fueling injector.
657-21 Engine Injector Cylinder #07 : Data Drifted Low	7-21 Cylinder #7 Injector : Data Drifted Low	The ECM has detected over fueling injector.
658-2 Engine Injector Cylinder #08 : Erratic, Intermittent, or Incorrect	8-2 Cylinder #8 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
658-5 Engine Injector Cylinder #08 : Current Below Normal	8-5 Cylinder #8 Injector : Current Below Normal	The ECM detects an open circuit.
658-6 Engine Injector Cylinder #08 : Current Above Normal	8-6 Cylinder #8 Injector : Current Above Normal	The ECM detects a short circuit.
658-7 Engine Injector Cylinder #08 : Not Responding Properly	8-7 Cylinder #8 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
658-20 Engine Injector Cylinder #08 : Data Drifted High	8-20 Cylinder #8 Injector : Data Drifted High	The ECM has detected under fueling injector.
658-21 Engine Injector Cylinder #08 : Data Drifted Low	8-21 Cylinder #8 Injector : Data Drifted Low	The ECM has detected over fueling injector.
659-2 Engine Injector Cylinder #09 : Erratic, Intermittent, or Incorrect	9-2 Cylinder #9 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
659-5 Engine Injector Cylinder #09 : Current Below Normal	9-5 Cylinder #9 Injector : Current Below Normal	The ECM detects an open circuit.
659-6 Engine Injector Cylinder #09 : Current Above Normal	9-6 Cylinder #9 Injector : Current Above Normal	The ECM detects a short circuit.
659-7 Engine Injector Cylinder #09 : Not Responding Properly	9-7 Cylinder #9 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
659-20 Engine Injector Cylinder #09 : Data Drifted High	9-20 Cylinder #9 Injector : Data Drifted High	The ECM has detected under fueling injector.
659-21 Engine Injector Cylinder #09 : Data Drifted Low	9-21 Cylinder #9 Injector : Data Drifted Low	The ECM has detected over fueling injector.
660-2 Engine Injector Cylinder #10 : Erratic, Intermittent, or Incorrect	10-2 Cylinder #10 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
660-5 Engine Injector Cylinder #10 : Current Below Normal	10-5 Cylinder #10 Injector : Current Below Normal	The ECM detects an open circuit.
660-6 Engine Injector Cylinder #10 : Current Above Normal	10-6 Cylinder #10 Injector : Current Above Normal	The ECM detects a short circuit.
660-7 Engine Injector Cylinder #10 : Not Responding Properly	10-7 Cylinder #10 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
660-20 Engine Injector Cylinder #10 : Data Drifted High	10-20 Cylinder #10 Injector : Data Drifted High	The ECM has detected under fueling injector.
660-21 Engine Injector Cylinder #10 : Data Drifted Low	10-21 Cylinder #10 Injector : Data Drifted Low	The ECM has detected over fueling injector.
661-2 Engine Injector Cylinder #11 : Erratic, Intermittent, or Incorrect	11-2 Cylinder #11 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
661-5 Engine Injector Cylinder #11 : Current Below Normal	11-5 Cylinder #11 Injector : Current Below Normal	The ECM detects an open circuit.
661-6 Engine Injector Cylinder #11 : Current Above Normal	11-6 Cylinder #11 Injector : Current Above Normal	The ECM detects a short circuit.
661-7 Engine Injector Cylinder #11 : Not Responding Properly	11-7 Cylinder #11 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
661-20 Engine Injector Cylinder #11 : Data Drifted High	11-20 Cylinder #11 Injector : Data Drifted High	The ECM has detected under fueling injector.
661-21 Engine Injector Cylinder #11 : Data Drifted Low	11-21 Cylinder #11 Injector : Data Drifted Low	The ECM has detected over fueling injector.
662-2 Engine Injector Cylinder #12 : Erratic, Intermittent, or Incorrect	12-2 Cylinder #12 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
662-5 Engine Injector Cylinder #12 : Current Below Normal	12-5 Cylinder #12 Injector : Current Below Normal	The ECM detects an open circuit.
662-6 Engine Injector Cylinder #12 : Current Above Normal	12-6 Cylinder #12 Injector : Current Above Normal	The ECM detects a short circuit.
662-7 Engine Injector Cylinder #12 : Not Responding Properly	12-7 Cylinder #12 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
662-20 Engine Injector Cylinder #12 : Data Drifted High	12-20 Cylinder #12 Injector : Data Drifted High	The ECM has detected under fueling injector.
662-21 Engine Injector Cylinder #12 : Data Drifted Low	12-21 Cylinder #12 Injector : Data Drifted Low	The ECM has detected over fueling injector.
663-2 Engine Injector Cylinder #13 : Erratic, Intermittent, or Incorrect	13-2 Cylinder #13 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
663-5 Engine Injector Cylinder #13 : Current Below Normal	13-5 Cylinder #13 Injector : Current Below Normal	The ECM detects an open circuit.
663-6 Engine Injector Cylinder #13 : Current Above Normal	13-6 Cylinder #13 Injector : Current Above Normal	The ECM detects a short circuit.
663-7 Engine Injector Cylinder #13 : Not Responding Properly	13-7 Cylinder #13 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
663-20 Engine Injector Cylinder #13 : Data Drifted High	13-20 Cylinder #13 Injector : Data Drifted High	The ECM has detected under fueling injector.
663-21 Engine Injector Cylinder #13 : Data Drifted Low	13-21 Cylinder #13 Injector : Data Drifted Low	The ECM has detected over fueling injector.
664-2 Engine Injector Cylinder #14 : Erratic, Intermittent, or Incorrect	14-2 Cylinder #14 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
664-5 Engine Injector Cylinder #14 : Current Below Normal	14-5 Cylinder #14 Injector : Current Below Normal	The ECM detects an open circuit.
664-6 Engine Injector Cylinder #14 : Current Above Normal	14-6 Cylinder #14 Injector : Current Above Normal	The ECM detects a short circuit.
664-7 Engine Injector Cylinder #14 : Not Responding Properly	14-7 Cylinder #14 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
664-20 Engine Injector Cylinder #14 : Data Drifted High	14-20 Cylinder #14 Injector : Data Drifted High	The ECM has detected under fueling injector.
664-21 Engine Injector Cylinder #14 : Data Drifted Low	14-21 Cylinder #14 Injector : Data Drifted Low	The ECM has detected over fueling injector.
665-2 Engine Injector Cylinder #15 : Erratic, Intermittent, or Incorrect	15-2 Cylinder #15 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
665-5 Engine Injector Cylinder #15 : Current Below Normal	15-5 Cylinder #15 Injector : Current Below Normal	The ECM detects an open circuit.
665-6 Engine Injector Cylinder #15 : Current Above Normal	15-6 Cylinder #15 Injector : Current Above Normal	The ECM detects a short circuit.
665-7 Engine Injector Cylinder #15 : Not Responding Properly	15-7 Cylinder #15 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
665-20 Engine Injector Cylinder #15 : Data Drifted High	15-20 Cylinder #15 Injector : Data Drifted High	The ECM has detected under fueling injector.
665-21 Engine Injector Cylinder #15 : Data Drifted Low	15-21 Cylinder #15 Injector : Data Drifted Low	The ECM has detected over fueling injector.
666-2 Engine Injector Cylinder #16 : Erratic, Intermittent, or Incorrect	16-2 Cylinder #16 Injector : Erratic, Intermittent, or Incorrect	The ECM has detected that an injector or injectors are not responding as desired.
666-5 Engine Injector Cylinder #16 : Current Below Normal	16-5 Cylinder #16 Injector : Current Below Normal	The ECM detects an open circuit.
666-6 Engine Injector Cylinder #16 : Current Above Normal	16-6 Cylinder #16 Injector : Current Above Normal	The ECM detects a short circuit.
666-7 Engine Injector Cylinder #16 : Not Responding Properly	16-7 Cylinder #16 Injector : Not Responding Properly	The ECM has detected there is a problem with an injector.
666-20 Engine Injector Cylinder #16 : Data Drifted High	16-20 Cylinder #16 Injector : Data Drifted High	The ECM has detected under fueling injector.
666-21 Engine Injector Cylinder #16 : Data Drifted Low	16-21 Cylinder #16 Injector : Data Drifted Low	The ECM has detected over fueling injector.

Show/hide table




Illustration 1	g06305707

Show/hide table

Electrical Shock Hazard. The unit injector system uses 90 - 120 volts. The ECM sends this signal to the unit injectors. Do not come in contact with the unit injector harness connector while the engine is operating. Failure to follow this instruction could resulting in personal injury or death.

Show/hide table

NOTICE

If error ID $1100 for Fuel Rail Pressure Too High is received while trying to perform the "Injector Solenoid - Test", the pressure in the fuel system must be released. Refer to Testing and Adjusting, Fuel Rail Pressure - Release for additional information.

Show/hide table

Table 2
Troubleshooting Test Steps	Values	Results
1. Check for Codes A. Connect Cat^® Electronic Technician (ET) to the service tool connector. B. Determine if a code is active or logged.	Codes	Result: A -2 code is active or logged. Repair: A failed fuel injector has been detected. Perform the following procedure: 1. 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. 2. Verify that the "Fuel Rail Pressure" reading in Cat ET is 0 ± 8 MPa (1160 psi) prior to servicing the fuel system. 3. Replace the failed fuel injector. Proceed to Test Step 11. Result: A -5 code is active or logged. Proceed to Test Step 2. Result: A -6 code is active or logged. Proceed to Test Step 4. Result: A -7 code is active or logged. Proceed to Test Step 8. Result: A -20 or -21 code is active or logged. Repair: A failed fuel injector has been detected. Perform the following procedure: 1. 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. 2. Verify that the "Fuel Rail Pressure" reading in Cat ET is 0 ± 8 MPa (1160 psi) prior to servicing the fuel system. 3. Replace the failed fuel injector. Proceed to Test Step 11.
2. Check the External Engine Wiring Harness for an Open Circuit A. Turn the keyswitch to the OFF position. Note: A strong electrical shock hazard is present if the keyswitch is not turned off. B. Disconnect the connector at the pass through connector for the affected fuel injector. C. Fabricate a jumper wire that is long enough to create a test circuit across the harness connector at the cylinder head. Crimp connector pins to each end of the jumper wire. D. Connect the jumper wire between the following terminal locations: - Terminal 1 (supply) and Terminal 2 (return) Note: This test will effectively create a short circuit for the cylinder. E. Connect Cat ET. F. Use Cat ET Cat to perform the following fuel injector test: - "Injector Solenoid - Test" Note: Perform the test at least two times. G. Monitor the screens on Cat ET. H. Repeat this test for each affected circuit. Stop the "Injector Solenoid - Test" before handling the jumper wire. J. Restore the wiring to the original configuration.	Open Circuit	Result: Cat ET displays "Short" for the cylinder with the jumper wire. The external engine harness is OK. Remove the jumper wire. Connect the harness connectors. Proceed to Test Step 3. Result: Cat ET displays "Open" for the cylinder with the jumper wire. The ECM did not detect the jumper wire. There is an open circuit in the wiring harness. Repair: Repair or replace the connectors or wiring. Ensure that all the seals are properly in place and ensure that the connectors are coupled. Start the engine. Verify that the repair eliminated the problem. Return to service.
3. Check the Internal Engine Wiring Harness for an Open Circuit A. Turn the keyswitch to the OFF position. Note: A strong electrical shock hazard is present if the keyswitch is not turned off. B. Remove the valve cover for the affected fuel injector. C. Disconnect the connector at the affected fuel injector under the valve cover. D. Fabricate a jumper wire that is long enough to create a test circuit across the harness connector at the cylinder head. Crimp connector pins to each end of the jumper wire. E. Connect the jumper wire between the following terminal locations: - Terminal 1 (supply) and Terminal 2 (return) Note: This test will effectively create a short circuit for the cylinder. F. Connect Cat ET. G. Use Cat ET Cat to perform the following fuel injector test: - "Injector Solenoid - Test" Note: Perform the test at least two times. H. Monitor the screens on Cat ET. J. Repeat this test for each affected circuit. Stop the "Injector Solenoid - Test" before handling the jumper wire. K. Restore the wiring to the original configuration.	Open Circuit	Result: Cat ET displays "Short" for the cylinder with the jumper wire. Proceed to Test Step 6. Result: Cat ET displays "Open" for the cylinder with the jumper wire. The ECM did not detect the jumper wire. There is an open circuit in the internal injector harness. Repair: Repair or replace the connectors or wiring. Ensure that all the seals are properly in place and ensure that the connectors are coupled. Start the engine. Verify that the repair eliminated the problem. Return to service.
4. Check the Engine Harness for a Short Circuit A. Turn the keyswitch to the OFF position. Note: A strong electrical shock hazard is present if the keyswitch is not turned off. B. Remove the valve cover for the affected fuel injector. C. Disconnect the connector at the affected fuel injector under the valve cover. D. Connect Cat ET. E. Use Cat ET Cat to perform the following fuel injector test: - "Injector Solenoid - Test" Note: Perform the "Injector Solenoid - Test" at least two times. F. Monitor the screens on Cat ET. G. Repeat this test for each affected circuit. Stop the "Injector Solenoid - Test" before handling the jumper wire. H. Restore the wiring to the original configuration.	Short Circuit	Result: Cat ET displays "Short" for the affected cylinders. Proceed to Test Step 5. Result: Cat ET displays "Open" for the affected cylinders. An "Open" circuit in the wiring harness between the injector and the ECM has been detected. Repair: Refer to the appropriate wiring diagram. Repair or replace the wiring harness. Start the engine. Verify that the repair eliminated the problem. Return to service.
5. Check the External Engine Wiring Harness for a Short Circuit A. Turn the keyswitch to the OFF position. Note: A strong electrical shock hazard is present if the keyswitch is not turned off. B. Disconnect the connector at the pass through connector for the affected fuel injector. C. Connect Cat ET. D. Use Cat ET Cat to perform the following fuel injector test: - "Injector Solenoid - Test" Note: Perform the "Injector Solenoid Test" at least two times. E. Monitor the screens on Cat ET. F. Repeat this test for each affected circuit. Stop the "Injector Solenoid - Test" before handling the jumper wire. G. Restore the wiring to the original configuration.	Short Circuit	Result: Cat ET displays "Short" for the affected cylinders. The problem is a short circuit in the engine wiring harness between the pass through connector and the engine ECM. Repair: Repair or replace the engine wiring harness. Start the engine. Verify that the problem is resolved. Result: Cat ET displays "Open" for the cylinders The problem is a short circuit in the injector wiring harness between the pass through connector and the injector connector. Repair: Repair or replace the fuel injector wiring harness. Start the engine. Verify that the repair eliminated the problem. Return to service.
6. Check the External Engine Wiring Harness for a Short Circuit to Ground A. Turn the keyswitch to the OFF position. B. Disconnect the connector at the affected fuel injector at the pass through connector. C. Disconnect the connector of the injector that shares the power supply with the affected fuel injector at the pass through connector. D. Disconnect the appropriate wiring harness connector from the ECM. - For the left bank, disconnect the EL-C1 connector from the Engine ECM. - For the right bank, disconnect the ER-C2 connector from the Engine ECM. E. Measure the resistance between terminal 2 on the affected fuel injector connector and a known good ground. F. Measure the resistance between terminal 2 on the injector that shares the power supply with the affected fuel injector and a known good ground. Note: Refer to the appropriate wiring schematic to see which injectors share a power supply.	ECM	Result: There were less than 100 K ohms of resistance between terminal 2 on the injector connector and a known good ground on both injectors. A short circuit to ground has been detected in the wiring harness. Repair: Repair or replace the injector wiring harness. Start the engine. Verify that the repair eliminated the problem. Return to service. Result: There were more than 100 K ohms of resistance between terminal 2 on the injector connector and a known good ground on both injectors. Proceed to Test Step 7.
7. Check the Internal Engine Wiring Harness for a Short Circuit A. Turn the keyswitch to the OFF position. B. Remove the valve cover for the affected fuel injector. C. Disconnect the connector at the affected fuel injector under the valve cover. D. Remove the valve cover for the fuel injector that shares the power supply with the affected fuel injector. E. Disconnect the connector of the injector that shares the power supply with the affected fuel injector under the valve cover. F. Disconnect the appropriate wiring harness connector from the ECM. - For the left bank, disconnect the EL-C1 connector from the Engine ECM. - For the right bank, disconnect the ER-C2 connector from the Engine ECM. G Measure the resistance between terminal 2 on the affected fuel injector and a known good ground. H. Measure the resistance between terminal 2 on the fuel injector that shares the power supply with the affected fuel injector and a known good ground. Note: Refer to the appropriate wiring schematic to see which injectors share a power supply.	Short Circuit	Result: There were less than 100 K ohms of resistance between terminal 2 connector on the injector connector and a known good ground. A short circuit to ground has been detected in the internal wiring harness. Repair: Repair or replace the injector wiring harness. Start the engine. Verify that the repair eliminated the problem. Return to service. Result: There were more than 100 K ohms of resistance between terminal B on the injector connector and a known good ground. Repair: A failed fuel injector has been detected. Perform the following procedure: 1. 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. 2. Verify the "Fuel Rail Pressure" in Cat ET is 0 ± 8 MPa (0.0 ± 1160 psi) prior to servicing the fuel system. 3. Replace the affected fuel injector. Start the engine. Verify that the repair eliminated the problem. Return to service.
8. Check the Enhanced Troubleshooting Indicator (ETI) A. Turn the keyswitch to the ON position. B. Connect Cat ET. C. Determine which ETI is present.	ETI Code	Result: An ETI of 1 is present. Proceed to Test Step 9. Result: An ETI of 2, 3, or 4 is present. Repair: A failed fuel injector has been detected. Perform the following procedure: 1. 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. 2. Verify the "Fuel Rail Pressure" in Cat ET is 0 ± 8 MPa (0.0 ± 1160 psi) prior to servicing the fuel system. 3. Replace the affected fuel injector. Proceed to Test Step 11. Result: An ETI of 5 is present. Proceed to Test Step 11.
9. Check for a Leaking Accumulator - Quill Tube A. Turn the keyswitch to the OFF position. B. Release the pressure in the high-pressure rail by loosening the end plug on one of the last two fuel accumulators - quill tubes. Refer to Testing and Adjusting, "Fuel Rail Pressure - Release" for instructions on how to release the pressurized fuel. C. Verify the "Fuel Rail Pressure" in Cat ET is 0 ± 8 MPa (0.0 ± 1160 psi) prior to servicing the fuel system. D. Check the torque on each one of the affected cylinders high-pressure fuel lines and accumulator - quill tubes. E. Check the torque on each of the affected accumulator – quill studs and nuts. F. Connect Cat ET. G. Start the engine and allow the engine to run for at least 5 minutes. H. Use Cat ET to monitor the following: - -7 Code with an ETI of 1	Codes	Result: A -7 code with an ETI 1 came active during the engine operation. Proceed to Test Step 10. Result: A code did not become active. Proceed to Test Step 11.
10. Test the Fuel Injectors A. Connect Cat ET. B. Use Cat ET to perform the following fuel injector test: - "Cylinder Cut Out Test" C. Record the two cylinders which logged the fault. D. Clear the fault codes. E. Perform a manual cylinder cut out test on each of the cylinders that logged the -7 code. F. Use Cat ET to monitor the "Delivered Fuel Volume" while performing the cylinder cut out test.	Test	Result: The "Delivered Fuel Volume" dropped more for one injector when the fuel injector was cut out. Repair: A failed fuel injector has been detected. Perform the following procedure: 1. 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. 2. Verify the "Fuel Rail Pressure" in Cat ET is 0 ± 8 MPa (0.0 ± 1160 psi) prior to servicing the fuel system. 3. Replace the injector which caused the "Delivered Fuel Volume" to drop more. Proceed to Test Step 11.
11. Perform a "Fuel System Functional Test" A. Remove the accumulator leak detection plugs at the cylinders that were repaired. B. Connect Cat ET. C. Use Cat ET to perform the following test: - "Fuel System Functional Test"	Test	Result: The test was successfully. Reinstall the accumulator leak detection plugs. Reinstall the accumulator plugs. Return to service. Result: The test was not successfully. Contact the TC for assistance.

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).