HOLDER AS 2941858 - Caterpillar

System Operation Description:Use this procedure under the following situation:Use this procedure to determine if the fast idle switch is operating correctly.The following background information is related to this procedure:A fast idle switch (momentary switch) and a fast idle lamp can be installed. The operator can use the fast idle switch in either of the following ways:
Press and release the fast idle switch in order to use the engine speed that is programmed into the "Fast Idle RPM 1" parameter.
Use the accelerator pedal to accelerate the engine to the desired engine speed. Press and release the fast idle switch in order to maintain the engine speed at the desired engine speed.A second programmable parameter "Fast Idle RPM 2" provides a second engine rpm set speed. The Engine Control Module (ECM) will increase the engine speed from low idle to the engine speed that is programmed in the "Fast Idle RPM 1" parameter when the fast idle switch is pressed and then released. The ECM will set the engine speed to the rpm that is programmed in the "Fast Idle RPM 2" parameter when the fast idle switch is pressed and then released again.Input 18 (P1-40) is used as a switch input for fast idle operation. This feature does not require an input selection to be programmed to enable the switch input. A momentary connection between P1- 40 and a sensor common will initiate the fast idle operation. The "Fast Idle RPM 2" and/or "Fast Idle RPM 1" parameters must be programmed to the desired engine operating speeds.The engine rpm set speed will not be maintained if any of the following actions occur:
The service brake is depressed.
The clutch pedal is depressed.
The neutral switch indicates that the transmission is in gear.A lamp can be connected to output 9 in order to indicate when fast idle is in operation. The "Fast Idle Enable Lamp" parameter must be programmed to "J1/P1:21" or "J1/P1:31" to enable the lamp operation.
Illustration 1 g00770407
Typical circuit schematic
The return wire may be connected to P1-3, P1-5, or P1-18.
Illustration 2 g01151104
Pin locations on ECM connector
(P1-5) AP sensor/switch common
(P1-40) Input 18 Test Step 1. Check the Electrical Connectors and the Wiring
Thoroughly inspect the ECM vehicle harness connector J1/P1, terminal 40, and the firewall bulkhead connectors. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the fast idle switch circuit. The wires are on the following terminals:
J1/P1-40
J1/P1-5
Check the ECM connector (allen head screw) for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Check the harness and the wiring for abrasion and pinch points from the battery to the ECM. Then, check from the ignition key switch to the ECM. Refer to Illustration 2 for terminal locations for 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 or of pinch points.Results:
OK - Proceed to Test Step 2.
Not OK