Electronic Modular Control Panel II (EMCP II) For MUI Engines Caterpillar

Illustration 1	g00616030
System Schematic For Engine Control Switch (ECS)

The Engine Control Switch (ECS) is used by the operator for manually controlling the engine. The ECS has four positions and each position connects to a corresponding input of the GSC. The selected position of the ECS connects the corresponding input of the GSC to ground ("B-"). At any time, only one of these four positions is connected to ground ("B-").

Each position of the ECS places the engine in a different mode. The following information contains the four positions and the corresponding engine modes.

OFF/RESET - The engine is shut down and the GSC is reset. The upper display and the fault indicators on the left side are temporarily cleared. The GSC turns OFF unless a jumper is installed from terminal 6 of the ECS to terminal 9 of the ECS.

AUTO - The engine will start when the customer's remote start/stop contact closes the start input on the GSC to the ground ("B-"). the engine will start. The engine starts when the customer communication module (CCM) sends a remote start command. At this time, the GSC starts the engine and the engine runs normally until the remote start/stop contact opens. The engine stops when the customer communication module (CCM) sends a remote signal to stop. Then, the engine enters a time of cooldown before the engine is shut down. The GSC shows faults on the upper display and on the fault indicators as the faults occur. The GSC is ON with the ECS in this position.

MAN/START - The engine starts and runs until the operator turns the ECS to OFF/RESET, to COOLDOWN/STOP or until the GSC detects a fault shutdown. The GSC shows faults on the upper display and on the fault indicators as the faults occur. The GSC is ON with the ECS in this position.

COOLDOWN/STOP - The engine maintains rated speed for the cooldown period (programmable 0 to 30 minutes). After the cooldown period elapses, the engine is shut down. The GSC shows faults on the upper display and on the fault indicators as the faults occur. The GSC is ON with the ECS in this position.

Note: The remote start/stop contacts are connected to the GSC start input via the terminal TS1-14 in the generator housing. Before troubleshooting, disconnect the remote start contacts by removing the wire from terminal TS1-14.

Note: Diagnostic codes are created when the harness connector (40 contact) is disconnected from the GSC during these troubleshooting procedures. Clear these created faults after the particular fault is corrected. In a properly operating system, when the harness connector is removed from the GSC, the following diagnostic fault codes are recorded:

• CID 100 FMI 3 pressure sensor (engine oil)

• CID 110 FMI 3 temperature sensor (engine coolant)

• CID 111 FMI 3 fluid level sensor (engine coolant)

• CID 190 FMI 3 speed sensor (engine)

• CID 331 FMI 2 switch (engine control)

• CID 336 FMI 2 switch (engine control)

Procedure

The following conditions could be a possible cause of this diagnostic code:

• None of the GSC inputs from the ECS are connected to ground.

• More than one of the GSC inputs from the ECS is connected to ground ("B-") at the same time.

The one exception is the start input. The start input of the GSC is also connected to the remote start/stop contact. The start input is controlled by the customer. Therefore, the GSC accepts a connection to ground ("B-") at the start input. This connection is accepted with a combination of any other input for the ECS.

The CID 331 FMI 2 is the only fault for the ECS that is detected by the GSC. Clear the diagnostic code from the fault log after troubleshooting is complete. The GSC treats this diagnostic code as a shutdown fault. Use these procedures for an active fault or an inactive fault.

1. Check for an open circuit.

   When you are performing this step, see the preceding System Schematic.

   1. If equipped, disconnect the remote start/stop contacts by removing the wire from terminal TS1-14. Reconnect after troubleshooting is complete.

   2. Disconnect the harness connector from the GSC.

   3. For each position of the ECS, the corresponding contact of the GSC harness connector, is the only contact that is connected to ground ("B-").

   4. Place the ECS in the OFF/RESET position. At the GSC harness connector, measure the resistance from contact 39 to the "B-" terminal of the relay module. The resistance should be 5 ohms or less. Measure the resistance from contacts 32, 33 and 40 to the "B-" terminal. The resistance should be greater than 5000 ohms.

   5. Place the ECS in the AUTO position. At the GSC harness connector, measure the resistance from contact 40 to the "B-" terminal of the relay module. The resistance should be 5 ohms or less. Measure the resistance from contacts 32, 33 and 39 to the "B-" terminal. The resistance should be greater than 5000 ohms.

   6. Place the ECS in the MAN/START position. At the GSC harness connector, measure the resistance from contact 33 to the "B-" terminal of the relay module. The resistance should be 5 ohms or less. Measure the resistance from contacts 32, 39 and 40 to the "B-" terminal. The resistance should be greater than 5000 ohms.

   7. Place the ECS in the COOLDOWN/STOP position. At the GSC harness connector, measure the resistance from contact 32 to the "B-" terminal of the relay module. The resistance should be 5 ohms or less. Measure the resistance from contacts 33, 39 and 40 to the "B-" terminal. The resistance should be greater than 5000 ohms.

      Expected Result: For each measurement of steps 1.d, 1.e, 1.f and 1.g, the resistance should be as stated in the step.

      Results:

      • OK - All resistance measurements are correct. The circuits in the harness are NOT open. To further check the harness, go to Testing And Adjusting, "Electrical Connector - Inspect". STOP.

      • NOT OK - One or more of the resistance measurements are NOT correct. The ECS is faulty or the harness wiring with the incorrect resistance measurement is open. Troubleshoot the ECS and/or repair the faulty harness wiring between ground ("B-") and the GSC connector. STOP.