Speed Control (Engine Speed Switch) - Test
Use this procedure to troubleshoot the electrical system if a problem is suspected with the circuit for the idle/rated switch.
Show/hide table
| |
| Illustration 1 | g03845607 |
Show/hide table
| Troubleshooting Test Steps | Value | Results |
|---|---|---|
1. Inspect Electrical Connectors and Wiring. A. Turn the engine control switch to the OFF position. B. Thoroughly inspect the J1/P1 connector. Thoroughly inspect the J17/P17 connector. The connectors should be free of abrasions, corrosion, and pinch points. Refer to Troubleshooting, "Electrical Connectors - Inspect". C. Perform a D. Check the allen head screw on each ECM connector for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect". E. Check the harness for abrasions and for pinch points from the battery to the ECM. |
Electrical connectors and wiring |
Result : The electrical connectors and wiring are OK. Proceed to Test Step 2. Result : The electrical connectors and wiring are NTO OK. Repair : Repair the connectors or the harness and/or replace the connectors or the harness. Ensure that all of the seals are correctly in place and ensure that the connectors are coupled. If the problem is not resolved, proceed to Test Step 2. |
2. Check the Switch Status with Cat® Electronic Technician (ET). A. Turn the engine control switch to the OFF position. B. Connect to the service tool connector. C. Turn the engine control switch to the ON position. The engine should remain in the OFF position. D. Observe the status of the idle/rated switch on Cat ET. Operate the idle/rated switch and observe the status. |
Engine control switch status |
Result : The shutdown switch status is OK. Repair : The shutdown input is functioning properly. Refer to Troubleshooting, "Electrical Connectors - Inspect" for further information. Result : The shutdown switch status is NOT OK. Proceed to Test Step 3. |
3. Short the Switch Inputs at the Switch. A. Turn the engine control switch to the OFF position. B. Disconnect the wires from the idle/rated switch. C. Turn the engine control switch to the ON position. The engine should remain in the OFF position. D. Connect and disconnect the wires for the idle/rated switch. Observe the status on Cat ET. |
Engine control switch status |
Result : The engine control switch status is OK. Repair : Check the switch terminals for corrosion or damage. If there is no corrosion or damage, replace the idle/rated switch. Result : The engine control switch status is NOT OK. Proceed to Test Step 4. |
4. Check for Engine Ground at the Switch. A. Disconnect the -Battery wire at the idle/rated switch. B. Measure the resistance between the- battery wire and engine ground. The resistance measures less than 10 Ohms. |
Engine ground |
Result : The engine ground is OK. Proceed to Test Step 5. Result : The engine ground is NOT OK. Repair : There is an open in the harness. Repair the harness or replace the harness. |
5. Check the Resistance through the Harness. A. Disconnect the wires from the idle/rated switch. Connect the two wires together without the switch. B. Disconnect J1/P1. C. Measure the resistance between P1-75 and P1-81. The resistance measures less than 10 Ohms. |
Harness |
Result : The harness is OK. Proceed to Test Step 6. Result : The harness is NOT OK. Repair : There is an open in the harness. Repair the harness or replace the harness. |
6. Check For Shorts In The Harness. A. Disconnect the wires for the idle/rated switch. Note : The wires should be isolated from each other. The wires should not be allowed to come in contact with the engine ground. B. Disconnect J1/P1. C. Measure the resistance between P1-75 and P1-81. The resistance measures more than 20,000 Ohms. |
Harness |
Result : The harness is OK. Proceed to Test Step 7. Result : The harness is NOT OK. Repair : There is a short in the harness. Repair the harness or replace the harness. |
7. Short the Switch Input at the ECM. A. Turn the engine control switch to the OFFposition. B. Remove the wire from connector P1-75. C. Turn the engine control switch to the ON position. Observe the status on Cat ET. D. Turn the engine control switch to the OFF position. Observe the status on the Cat ET. E. Insert a wire with a "Deutsch" socket terminal into P1-75. Connect the other end to engine ground. F. Turn the engine control switch to the ON position. Observe the status on Cat ET. G. Turn the engine control switch to the OFF position. Observe the status on Cat ET. |
Input switch |
Result : The input switch is OK. Repair : The harness is faulty. Repair the harness or replace the harness. Result : The input switch is NOT OK. Repair : The ECM is not reading the signal. Replace the ECM. |
Caterpillar Information System:
794 AC Off-Highway Truck Field Assembly Air Lines (Turbocharger) - Install
3512C Generator Set Engine Engine Oil Filter Housing - Remove and Install
3412 Generator Set Shutdown - Test
Cat® MineStar System A5:N2 Router Setup and Configuration Guide {7008, 7605} Cat® MineStar System A5:N2 Router Setup and Configuration Guide {7008, 7605}
C32 Marine Engines Aftercooler - Install
C32 Marine Engines Aftercooler - Remove
G3606 and G3608 Engines Prelubrication Oil Pump - Install
G3600 A4 Engines Manual Stop Procedure
G3600 A4 Engines Before Starting Engine
G3600 A4 Engines Product Lifting
3512C Generator Set Engine Engine Oil Pump - Remove and Install
G3600 A4 Engines Engine Stopping
Energy Storage System General Information
3412 Generator Set Speed Control (PWM) - Test
Energy Storage System Abbreviations and Acronyms
Energy Storage System Site Considerations
Energy Storage System Service Tools
Energy Storage System Site Inspection and Material Inventory
Energy Storage System Equipment
Energy Storage System Enclosure Placement and Anchoring
Energy Storage System Mechanical Assembly
Energy Storage System Cathode Fan Wiring
Energy Storage System Power Cable Wiring
Energy Storage System Enclosure Fan Wiring