C7 and C9 Petroleum Engines Caterpillar

Use this procedure in order to troubleshoot the ether system or use this procedure if any one of the diagnostic codes in Table 1 is active or easily repeated.

Before you test the ether injection system, remove the ether canister from the system.

The ether injection system is used to improve cold weather starting of the engine. The ECM controls the ether injection system during the start cycle. The ether injection system has two modes of operation:

Automatic mode - In the automatic mode, if the engine coolant temperature is below 0 °C (32 °F) and the engine speed is zero rpm, the ether injection system is actuated by the ECM. Ether is injected continuously until the engine starts (50 rpm below low idle). Ether will continue to be injected for a short duration after engine starting that is dependent on ambient conditions.

Manual mode - In the manual mode, the ECM energizes the ether solenoid for a single shot of ether.

Manual mode is activated by pressing the ether starting aid switch. A short burst of ether is injected when the ether starting aid switch is pressed. In the manual mode, the ether injection system can be enabled if all of the following conditions are met:

• The ether starting aid switch is pressed.

• The intake manifold air temperature is less than 0 °C (32 °F).

• There are no active diagnostic codes for both the engine coolant temperature sensor and the intake manifold air temperature sensor.

If a problem is suspected with the ether starting aid switch, refer to Troubleshooting, "Switch Circuits - Test".

Test Mode - A test mode is available in Caterpillar Electronic Technician (ET). The test mode allows the technician to activate the ether system. The test is functional when the engine speed is zero rpm. The ether injection solenoid is activated for a ten second duration when the test is activated. The test can be found in the "Override Parameters" screen in Cat ET.

Illustration 1	g01382232
Schematic of the ether injection system

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The connection of any electrical equipment and the disconnection of any electrical equipment may cause an explosion hazard which may result in injury or death. Do not connect any electrical equipment or disconnect any electrical equipment in an explosive atmosphere.

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Breathing ether vapors or repeated contact of ether with skin can cause personal injury. Personal injury may occur from failure to adhere to the following procedures. Use ether only in well ventilated areas. Do not smoke while changing ether cylinders. Use ether with care to avoid fires. Do not store replacement ether cylinders in living areas or in the operator's compartment. Do not store ether cylinders in direct sunlight or at temperatures above 49 °C (120 °F). Discard cylinders in a safe place. Do not puncture or burn cylinders. Keep ether cylinders out of the reach of unauthorized personnel. To avoid possible injury, be sure the brakes are applied and all controls are in Hold or Neutral when starting the engine.

Test Step 1. Inspect the Electrical Connectors and the Wiring

1. Remove electrical power from the ECM.
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   Illustration 2	g01388294
   Engine view (typical example) (1) J1/P1 ECM connectors

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   Illustration 3	g01456393

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   Illustration 4	g01170983
   Ether starting aid group (typical example) (2) Ether injection solenoid

2. Thoroughly inspect connector (1). Also, thoroughly inspect the connectors for solenoid (2). Refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect".
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   Illustration 5	g01212950
   P1 terminals for the ether injection system (P1-10) Ether injection solenoid (P1-22) Override switch

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   Illustration 6	g01212957
   P61 terminals for the ether injection system (22) Ether injection solenoid (38) Override switch

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   Illustration 7	g01155187
   Terminal locations at the harness connector for the ether solenoid (1) Ether injection solenoid (2) Chassis ground

3. Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the ether injection system.

4. Check the allen head screw on each ECM connector for the proper torque. Also check the allen head screw on the customer connector for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.

5. Check the harness and the wiring for abrasion and for pinch points from the ether injection solenoid to the ECM.

Expected Result:

All connectors, pins, and sockets are completely coupled and/or inserted, and the harness and wiring are free of corrosion, of abrasion and of pinch points.

Results:

• OK - The connectors and wiring appear to be OK. Proceed to Test Step 2.

• Not OK - The connectors and/or wiring are not OK.

  Repair: Repair the connectors and/or the wiring. Replace parts, if necessary. Verify that the problem is resolved.

  STOP

Test Step 2. Check the Ether Canister for Starting Fluid

1. Remove electrical power from the ECM.

2. Remove the ether canister from the ether valve. Determine if the canister contains fluid.

Expected Result:

The ether canister is not empty.

Results:

• OK - The ether canister is not empty. Do not install the ether canister. Proceed to Test Step 3.

• Not OK - The ether canister is empty.

  Repair: Replace the empty ether canister with a full ether canister. Verify that the original problem is resolved.

  STOP

Test Step 3. Check for Active Diagnostic Codes

Note: The ether canister must be removed prior to performing this procedure.

1. Connect Cat ET to the service tool connector. Refer to Troubleshooting, "Electronic Service Tools".

2. Restore electrical power to the engine ECM.

3. Proceed to the "Diagnostic Overrides" screen on Cat ET.

4. Activate the ether injection system. The system will activate for ten seconds.

5. Monitor the active diagnostic code screen on Cat ET. Check and record any active diagnostic codes.

   Note: Wait at least 30 seconds in order for the diagnostic codes to become active.

6. Look for a -5 diagnostic code or a -6 diagnostic code.

7. Remove electrical power from the engine ECM.

Expected Result:

No diagnostic codes are active.

Results:

• No active codes - Neither diagnostic code is active.

  Repair: The problem seems to be resolved. The problem may have been caused by a poor electrical connection. Carefully reinspect the connectors and the wiring. Refer to Troubleshooting, "Electrical Connectors - Inspect".

  STOP

• Not OK - A -5 code is active at this time. The ECM is detecting a low current condition in the circuit. Proceed to Test Step 5.

• Not OK - A -6 code is active at this time. The ECM is detecting excessive current in the circuit. Proceed to Test Step 4.

Test Step 4. Create an Open at the Harness Connector for the Ether Injection Solenoid

1. Disconnect the harness connector for the ether solenoid.

2. Restore electrical power to the engine ECM.

3. Proceed to the "Diagnostic Overrides" screen on Cat ET.

4. Activate the ether injection system. The system will activate for ten seconds.

5. Monitor the active diagnostic code screen on Cat ET. Look for an active -5 code.

   Note: Wait at least 30 seconds in order for the diagnostic codes to become active.

6. Remove electrical power from the engine ECM.

Expected Result:

A -5 code is now active.

Results:

• OK - A -6 code was active before the connector was disconnected. A -5 code became active after the connector was disconnected.

  Repair: The circuit for the ether solenoid is OK. Temporarily connect a new solenoid to the harness, but do not install the new solenoid. After connecting the new solenoid to the harness, verify that there are no active codes for the ether injection system.

  If there are no active codes for the ether injection system, permanently install the new solenoid. Clear any logged diagnostic codes.

  STOP

• Not OK - A -6 code was active before the connector was disconnected. The -6 code remained active after the connector was disconnected. There is a problem in the circuit for the ether injection solenoid. There may be a problem with the ECM. Leave the connector for the solenoid disconnected. Proceed to Test Step 6.

Test Step 5. Create a Short at the Connector for the Ether Injection Solenoid

1. Disconnect the harness connector for the ether solenoid.

2. Fabricate a jumper wire that is long enough to create a short circuit between terminal 1 and terminal 2 at the harness connector for the ether solenoid. Crimp connector pins to each end of the jumper wire.

3. Install the jumper wire between terminals 1 and 2 of the harness connector.

4. Restore electrical power to the engine ECM.

5. Proceed to the "Diagnostic Overrides" screen on Cat ET.

6. Activate the ether injection system. The system will activate for ten seconds.

7. Monitor the active diagnostic code screen on Cat ET. Look for an active -6 code.

   Note: Wait at least 30 seconds in order for the diagnostic codes to become active.

8. Remove electrical power from the engine ECM.

9. Remove the jumper wire from the harness connector.

Expected Result:

A -6 code is now active.

Results:

• OK - A -5 code was active before the jumper wire was installed. A -6 code became active after the jumper wire was installed.

  Repair: The engine harness and the ECM are OK. Temporarily connect a new solenoid to the harness, but do not install the new solenoid. Verify that there are no active diagnostic codes for the solenoid. If there are no active diagnostic codes for the solenoid after the installation of the new solenoid, permanently install the new solenoid. Clear any logged diagnostic codes.

  STOP

• Not OK - A -5 code was active before the jumper wire was installed. The -5 code remained active after the jumper wire was installed. Remove the jumper wire and connect the connector. Proceed to Test Step 6.

Test Step 6. Check the Operation of the ECM

1. Disconnect the J1/P1 ECM connectors.

2. Fabricate a jumper wire that is long enough to create a test circuit from the ECM connector to the engine ground stud. Crimp a connector socket to one end of the jumper wire.

3. Remove the wire from terminal location J1-10 (ether injection solenoid) at the ECM connector. Install the jumper wire into this terminal location.

4. Connect the J1/P1 ECM connectors.

5. Check the operation of the ECM by creating an open at the ECM:

   1. Hold the loose end of the jumper wire away from any ground source in order to create an open circuit condition.

   2. Restore electrical power to the ECM.

   3. Proceed to the "Diagnostic Overrides" screen on Cat ET.

   4. Activate the ether injection system. The system will activate for ten seconds.

   5. Monitor the active diagnostic code screen on Cat ET. Look for an active -5 code. Record the result.

      Note: Wait at least 30 seconds in order for the diagnostic codes to become active.

   6. Remove electrical power from the ECM.

6. Check the operation of the ECM by creating a short at the ECM.

   1. Short the jumper wire to the engine ground stud.

   2. Restore electrical power to the ECM.

   3. Proceed to the "Diagnostic Overrides" screen on Cat ET.

   4. Activate the ether injection system. The system will activate for ten seconds.

   5. Monitor the active diagnostic code screen on Cat ET. Look for an active -6 code. Record the result.

      Note: Wait at least 30 seconds in order for the diagnostic codes to become active.

7. Remove electrical power from the engine ECM.

8. Restore the wiring to the original configuration.

Expected Result:

A -5 code is active when the loose end of the jumper wire is open. A -6 code is active when the loose end of the jumper wire is grounded.

Results:

• OK - A -5 code is active when the loose end of the jumper wire is open. A -6 code is active when the loose end of the jumper wire is grounded.

  Repair: The ECM is operating properly. The problem is in the circuit for the ether solenoid. The problem may be in the harness between the ECM and the ether solenoid's harness connector or the harness between the ground connection and the ether solenoid's harness connector. Repair the connectors or wiring and/or replace the connectors or wiring. Refer to Illustration 1 for details.

  STOP

• Not OK - One of the following conditions exists: A -5 code is not active when the loose end of the jumper wire is open. A -6 code is not active when the loose end of the jumper wire is grounded.

  Repair: The ECM is not responding correctly. Replace the ECM. Refer to Troubleshooting, "ECM - Replace". Verify that the problem is resolved.

  STOP