C8.7 and C12.9 Marine Engines Caterpillar

Injector Solenoid - Test

Usage:

C8.7 CS7

This procedure covers the following codes:

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Table 1
Diagnostic Trouble Codes for the Circuit for the Injector Solenoids
J1939 Code and Description		Notes
651-5 Engine Injector Cylinder #01 : Current Below Normal		These diagnostic codes are designed to indicate an open circuit (low current) in either the solenoid or the wiring for the electronic unit injector in the applicable cylinder. The Electronic Control Module (ECM) detects the following conditions: A low current condition (open circuit) for the applicable cylinder for at least three attempts to actuate the solenoid. The ECM will log the diagnostic code. The engine will have low power and/or rough running. An open circuit will prevent the operation of the common rail injector.
652-5 Engine Injector Cylinder #02 : Current Below Normal
653-5 Engine Injector Cylinder #03 : Current Below Normal
654-5 Engine Injector Cylinder #04 : Current Below Normal
651-6 Engine Injector Cylinder #01 : Current Above Normal		These diagnostic codes are designed to indicate a short circuit (high current) in either the solenoid or the wiring for the electronic unit injector in the applicable cylinder. The ECM detects the following conditions: A high current condition (short circuit) for the applicable cylinder for at least five attempts to actuate the solenoid. The ECM will log the diagnostic code. The engine will have low power and/or rough running. A short circuit will prevent the operation of the electronic unit injector.
652-6 Engine Injector Cylinder #02 : Current Above Normal
653-6 Engine Injector Cylinder #03 : Current Above Normal
654-6 Engine Injector Cylinder #04 : Current Above Normal
2797-6 Engine Injector Group 1 : Current Above Normal		The ECM detects the following conditions: A short circuit condition in the driver for injector 1 and injector 4. The fault is present for at least five attempts to actuate the driver. The ECM will log the diagnostic code. The engine will have low power and/or rough running. The engine may shut down. A short circuit will prevent the operation of the two electronic unit injectors.
2797-7 Engine Injector Group 1 : Not Responding Properly		The ECM is unable to actuate any of the injectors. The engine will be derated. The engine will shut down or the engine will be unable to start.
2797-9 Engine Injector Group 1: Abnormal Update Rate		The ECM is reporting an internal failure. Replace the engine ECM.
2798-6 Engine Injector Group 2 : Current Above Normal		The ECM detects the following conditions: A short circuit condition in the driver for injector 2 and injector 3. The fault is present for at least five attempts to actuate the driver. The ECM will log the diagnostic code. The engine will have low power and/or rough running. The engine may shut down. A short circuit will prevent the operation of the two electronic unit injectors.

An electrical fault can prevent the electronic unit injector from operating. An open circuit or a short circuit in the ECM that is unique to one electronic unit injector will prevent that common rail injector from operating. An open circuit or a short circuit in common wiring within the ECM can prevent the two electronic unit injectors that share that common wiring from operating. Injector 1 and injector 4 share common wiring within the ECM. Injector 2 and injector 3 share common wiring within the ECM.

Perform this procedure under conditions that are identical to the conditions that exist when the fault occurs. Typically, faults with the injector solenoid occur when the engine is warmed up and/or when the engine is under vibration (heavy loads).

These engines have common rail injectors. The ECM sends a pulse to each injector solenoid. The pulse is sent at the correct time and at the correct duration for a given engine load and speed. The solenoid is mounted on top of the fuel injector body.

If an open circuit is detected in the solenoid circuit, a diagnostic code is generated. The ECM continues to try to fire the injector. If a short circuit is detected, a diagnostic code is generated. The ECM will periodically try to fire the injector. If the short circuit remains, this sequence of events will be repeated until the fault is corrected.

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Electrical Shock Hazard. The electronic unit injectors use DC voltage. The ECM sends this voltage to the electronic unit injectors. Do not come in contact with the harness connector for the electronic unit injectors while the engine is operating. Failure to follow this instruction could result in personal injury or death.

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Table 2
Troubleshooting Test Steps	Values	Results
1. Inspect Electrical Connectors and Wiring A. Turn the keyswitch to the OFF position. A strong electrical shock hazard is present if the keyswitch is not turned OFF. B. Thoroughly inspect the connectors at the injectors. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details. C. Inspect the terminals on the P1/J1 ECM connector and all other connectors associated with the injector solenoid circuits. D. Perform a 30 N (6.7 lb) pull test on each of the wires in the ECM connector that are associated with injector solenoids. E. Check the harness and wiring for abrasion and for pinch points from the injectors to the ECM.	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. Proceed to Test Step 2.
2. Check for Active Diagnostic Codes A. Connect the electronic service tool to the diagnostic connector. B. Start the engine. C. Allow the engine to warm up to the normal operating temperature. D. Stop the engine. E. Turn the keyswitch to the ON position. Note: Wait at least 30 seconds for activation of the diagnostic codes. F. Use the electronic service tool in order to verify if any of the diagnostic codes that are listed in Table 1 are active or recently logged.	Diagnostic codes	Result: An -5 diagnostic code is active or recently logged. Note the cylinders that the codes are applicable to. Proceed to Test Step 3. Result: An -6 diagnostic code is active or recently logged. Note the cylinders that the codes are applicable to. Proceed to Test Step 5. Result: A 2797-7 diagnostic code is active. Proceed to Test Step 7.
3. Create a Short at the Injector Connector A. Turn the keyswitch to the OFF position. A strong electrical shock hazard is present if the keyswitch is not turned OFF. B. Disconnect the connector from the suspect injector. C. Fabricate a jumper wire 100 mm (4 inch) long. D. Install the jumper wire between terminal 1 and terminal 2 on the harness connector for the suspect injector. E. Start the engine. Wait at least 30 seconds for activation of the diagnostic codes. F. Use the electronic service tool to check for active diagnostic codes. G. Turn the keyswitch to the OFF position. H. Remove the jumper wire.	Diagnostic codes	Result: A -6 diagnostic code was active with the jumper installed. Repair: Thoroughly inspect the electrical connector on the suspect injector and the harness connector for the suspect injector. Ensure that the connectors are free from corrosion. Reconnect the connector for the suspect injector. Start the engine. If the fault is still present, replace the faulty injector. Refer to Disassembly and Assembly, "Electronic Unit Injector - Remove" and Disassembly and Assembly, "Electronic Unit Injector - Install". Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault. Result: A -5 diagnostic code is still present with the jumper installed. Proceed to Test Step 4.
4. Create a Short at the ECM Connector A. Turn the keyswitch to the OFF position. A strong electrical shock hazard is present if the keyswitch is not turned OFF. B. Disconnect the P2 connector. C. Fabricate a jumper wire 100 mm (4 inch) long. D. Install the jumper wire between the supply and return pins for the suspect cylinder on the J2 connector. E. Turn the keyswitch to the ON position. Wait at least 30 seconds for activation of the diagnostic codes. Note: Diagnostic codes for all of the engine sensors will be active with the P2 connector disconnected. Ignore all other codes and only look for codes relating to the suspect injector. F. Use the electronic service tool to check for active diagnostic codes. G. Turn the keyswitch to the OFF position. H. Remove the jumper wire.	Diagnostic codes	Result: A -6 diagnostic code is active with the jumper installed. The fault is in the wiring for the suspect injector. Repair: Check all wiring between the suspect injector and the ECM. Refer to the Electrical Schematic for the engine. Replace the faulty wiring. Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault. Result: A -5 diagnostic code is still active with the jumper installed. Proceed to Test Step 7.
5. Create an Open Circuit at the Injector Connector or Connectors A. Turn the keyswitch to the OFF position. A strong electrical shock hazard is present if the keyswitch is not turned OFF. B. Disconnect the connector for any suspect injectors. C. Turn the keyswitch to the ON position. Wait at least 30 seconds for activation of the diagnostic codes. D. Use the electronic service tool to check for active diagnostic codes. E. Turn the keyswitch to the OFF position.	Diagnostic codes	Result: A -5 diagnostic code is active with the injectors disconnected. Repair: Thoroughly inspect the electrical connectors on the suspect injectors and the harness connector for the suspect injectors. Ensure that the connectors are free from corrosion. Reconnect the connector for the injectors. Start the engine. If the fault is still present, replace the faulty injectors. Refer to Disassembly and Assembly, "Electronic Unit Injector - Remove" and Disassembly and Assembly, "Electronic Unit Injector - Install". Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault. Result: A -6 diagnostic code is still active with the injectors disconnected. Proceed to Test Step 6.
6. Create an Open Circuit at the ECM Connector A. Turn the keyswitch to the OFF position. A strong electrical shock hazard is present if the keyswitch is not turned OFF. B. Disconnect connector P2 from the ECM. C. Thoroughly inspect the P2 connector. Refer to Troubleshooting, "Electrical Connectors - Inspect". D. Turn the keyswitch to the ON position. Wait for at least 30 seconds for activation of the diagnostic codes. Note: Diagnostic codes for all of the engine sensors will be active with the P2 connector disconnected. Ignore all other diagnostic codes and only look for codes relating to the suspect injectors. E. Use the electronic service tool to check for active diagnostic codes. F. Turn the keyswitch to the OFF position.	Diagnostic Codes	Result: A -5 diagnostic code is active with the P2 connector disconnected. The fault is in the wiring for the suspect injector. Repair: Check all wiring between the suspect injector and the ECM. Refer to the Electrical Schematic for the engine. Replace the faulty wiring. Use the electronic service tool to clear all logged diagnostic codes and verify that the repair eliminates the fault. Result: A -6 diagnostic code is still active with the P2 connector disconnected. Proceed to Test Step 7.
7. Check if a Replacement ECM Eliminates the Fault A. Contact the Dealer Solution Network (DSN). B. If the DSN recommends the use of a replacement ECM, install a replacement ECM. Refer to Troubleshooting, "ECM - Replace". C. Use the electronic service tool to recheck the system for active diagnostic codes.	Diagnostic codes	Result: There are no active diagnostic codes with the replacement ECM. Repair: Reconnect the suspect ECM. If the fault returns with the suspect ECM, replace the ECM. Use the electronic service tool in order to clear all logged diagnostic codes and then verify that the repair eliminates the fault. Result: The diagnostic code is still present with the replacement ECM. Contact the DSN.