3512B Marine Auxiliary Engine Caterpillar

The Electronic Control Module (ECM) receives four input signals from the ECS. The input signals allow the control to determine the mode of operation. The ECS can operate in four modes: OFF/RESET, BLACK START ENABLE, STOP and DGCP START ENABLE.

When the ECS is set to the OFF/RESET position, the START/RUN/STOP input is open and the ECS in BLACK START input is open. The ECM is not powered. Engine operation will stop when the ECS is switched to this position.

When the ECS is set to the DGCP START ENABLE position, the START/RUN/STOP input is open. The ECM is powered. If the SNORKLE SYSTEM SHUTDOWN DEVICE is closed, the engine start sequence will begin.

When the ECS is set to the BLACK START ENABLE position, the START/RUN/STOP input is open and the ECS in BLACK START input is closed. The ECM will begin the engine start sequence after the BLACK START PUSH BUTTON is depressed.

When the ECS is set to the STOP position, the START/RUN/STOP input and the ECS in BLACK START input are open. The ECM will shut down the engine.

If the signals from the START/RUN/STOP input are opposite, the ECM determines that one of the signals is faulty. The ECM ignores the signals until power is cycled to the ECM.

If this occurs, the engine must be cranked manually. Use the Manual Crank Switch which is located inside the Electronic Instrument Panel. When the engine is shut down, the ECS must be placed in the OFF/RESET position. This will disconnect power to the ECM. A CID-FMI will be active until the ECM is powered down. The parameter for the Ignition Switch will display "ABNORMAL DATA" until power to the ECM is cycled.

If the SNORKEL SYSTEM SHUTDOWN DEVICE is closed and the ECS is in the DGCP START ENABLE position, the engine will start. The parameter for the switch will display "ON" or "OFF". This parameter is available on the Caterpillar Electronic Technician (ET) only when the ECS is in the DGCP START ENABLE position.

If the ECS is in the BLACK START ENABLE position, the parameter for the switch will display "BLACK START". The parameter for the BLACK START PUSH BUTTON LAMP will display "ON". Once the BLACK START PUSH BUTTON is depressed the parameter will display "ON" and the engine will start. The parameters can be viewed on the Cat ET only when the ECS is in the BLACK START ENABLE position.

Illustration 1	g00852014

Test Step 1. Check for Connector Damage

1. Turn the circuit breaker for the battery to the OFF position.

2. Turn the ECS to the OFF/RESET position.

3. Check connectors and wiring for the following problems: damage, corrosion, abrasion and incorrect attachment.

Expected Result:

The connectors and wiring should be free of the following problems: damage, corrosion, abrasion and incorrect attachment.

Results:

• OK - The connectors and wiring are free of problems. Proceed to test step 2.

• Not OK - The connectors and wiringare not free of problems.

  Repair: Repair the connectors or wiring and/or replace the connectors or wiring. If necessary, replace the ECS.

  Stop.

Test Step 2. Check the Status of the Switch.

1. Turn the circuit breaker for the battery to the ON position.

2. Turn the circuit breaker for the Mag Relay of the Starting Motor System to the OFF position.

3. Activate the emergency stop switch. This will prevent the engine from starting during the following tests.

4. Turn the ECS to the STOP position.

5. Connect the Cat ET to the service tool connector.

6. Observe the parameter for the ignition switch on the Cat ET.

Expected Result:

The parameter for the ignition switch should read "STOP".

Results:

• OK - The parameter for the ignition switch displays"STOP". The ECS is functioning correctly. Proceed to test step 3.

• Not OK - The status for the ignition switch does not display "STOP". Proceed to test step 4.

Test Step 3. Check the Status of the Switch.

1. Turn the ECS to the START position.

2. Observe the parameter for the ignition switch on the Cat ET.

Expected Result:

The parameter for the ignition switch should read "RUN".

Results:

• OK - The parameter for the ignition switch displays "RUN". The ECS is working correctly. Proceed to test step 5.

• Not OK - The status of the Ignition Switch does not display "RUN". Proceed to test step 4.

Test Step 4. Install a Jumper Wire.

1. Turn the ECS to the OFF/RESET position.

2. Disconnect ECM connector P1. Remove P1-14, P1-8 and P1-29.

3. Fabricate a jumper wire.

4. Install the jumper wire at P1. Connect P1-14 and P1-8 to P1-29. Reconnect P1.

5. Turn the ECS to the STOP position.

6. Observe the parameter for the ignition switch on the Cat ET.

7. Turn the ECS to the OFF/RESET position and remove the jumper wire.

Expected Result:

The parameter for the ignition switch should display "RUN" while the jumper wire is installed. The parameter for the ignition switch should display"STOP" when the jumper wire is removed.

Results:

• OK - The parameter for the ignition switch displays the proper status. The problem is not with the ECM. Proceed to test step 6.

• Not OK - The parameter for the ignition switch does not display the proper status.

  Repair: Replace the ECM. Perform the diagnostic procedure Troubleshooting, "Replacing the ECM".

  Stop.

Test Step 5. Check the Status of the Switch.

1. Turn the ECS to BLACK START ENABLE.

2. Observe the parameters for the ignition switch on the Cat ET.

Expected Result:

The parameter for the ignition switch should read "BLACK START".

Results:

• OK - The parameter for the ignition switch displays "BLACK START".

  Repair: The ECS is working correctly.

  Stop.

• Ignition Switch Not OK - The parameter for the Ignition Switch does not display "BLACK START".

  Repair: Replace the ECM. Perform the diagnostic procedure Troubleshooting, "Replacing the ECM".

  Stop.

Test Step 6. Check Switches and Wiring.

1. Turn the ECS to the OFF position.

2. Disconnect ECM connector J1/P1.

3. Measure the resistance between the digital return P1-29 and the Start/Run/Stop Input 1 P1-8.

4. Measure the resistance between the digital return P1-29 and the Start/Run/Stop Input 2 P1-14.

5. Turn the ECS to the STOP position and repeat the above two measurements.

Expected Result:

The resistance should be greater than 20,000 Ohm.

Results:

• OK - The resistance is greater than 20,000 Ohm. Proceed to test step 9.

• Not OK - The resistance is less than 20,000 Ohm. There is a short circuit in the ECS.

  Repair: Repair the connectors or wiring and/or replace the connectors or wiring. If necessary, replace the ECS.

  Stop.

Test Step 7. Check the Switches and Wiring.

1. Turn the ECS to the AUTO position with the Remote START/STOP Switch in the STOP position.

2. Measure the resistance between the digital sensor return P1-29 and the Start/Run/Stop Input 1 P1-8.

3. Measure the resistance between the digital sensor return P1-29 and the Start/Run/Stop Input 2 P1-14.

Expected Result:

The resistance should be greater than 20,000 Ohms.

Results:

• OK - The resistance is greater than 20,000 Ohms. The ECS appears to be functioning properly. Proceed to test step 10.

• Not OK - The resistance is less than 20,000 Ohms. There is a short circuit in the ECS.

  Repair: Repair the connectors or wiring and/or replace the connectors or wiring. If necessary, replace the ECS.

  Stop.

Test Step 8. Install a Jumper Wire.

1. Turn the ECS to the OFF/RESET position.

2. Disconnect ECM connector P1.

3. Remove the wires from P2-01 and P1-29.

4. Fabricate a jumper wire.

5. Install the jumper wire at P1 and P2. Connect P2-01 to P1-29. Reconnect P1.

6. Turn the circuit breaker for the battery to the ON position.

7. Turn the ECS to the STOP position.

8. Observe the parameter for the ignition switch on the Cat ET.

9. Turn the ECS to the OFF/RESET position.

10. Remove the jumper wire.

Expected Result:

The parameter for the ignition switch should read "BLACK START" while the jumper wire is installed. The parameter for the ignition switch should read "STOP" when the jumper wire is removed.

Results:

• OK - The parameter for the ignition switch is displaying the proper status.

  Repair: The ECS is functioning correctly at this time.

  Stop.

• Not OK - The parameter for the ignition switch does not display the correct status.

  Repair: Replace the ECM. Perform the diagnostic procedure Troubleshooting, "Replacing the ECM".

  Stop.

Test Step 9. Check Switches and Wiring.

1. Turn the ECS to the DGCP START ENABLE position.

2. Check that the snorkel shutdown device is not energized.

3. Measure the resistance between P1-29 and P1-8.

4. Measure the resistance between P1-29 and P1-14.

Expected Result:

The resistance should be greater than 20,000 Ohms.

Results:

• OK - The resistance is greater than 20,000 Ohms. Proceed to test step 7.

• Not OK - The resistance is not greater than 20,000 Ohms.

  Repair: Repair the connectors or wiring and/or replace the connectors or wiring. If necessary, replace the ECS.

  Stop.

Test Step 10. Check the Switches and Wiring.

1. Turn the ECS to the DGCP START ENABLE position.

2. Check that the snorkel shutdown device is energized.

3. Measure the resistance between P1-29 and P1-8.

4. Measure the resistance between P1-29 and P1-14.

5. Turn the ECS to the BLACK START ENABLE position.

6. Check that the snorkel shutdown device is energized.

7. Measure the resistance between P1-29 and P1-8.

8. Measure the resistance between P1-29 and P1-14.

Expected Result:

The resistance should be greater than 20,000 Ohms.

Results:

• OK - The resistance is greater than 20,000 Ohms. Proceed to test step 8.

• Not OK - The resistance is not greater than 20,000 Ohms.

  Repair: Repair the connectors or wiring and/or replace the connectors or wiring. If necessary, replace the ECS.

  Stop.