Service Brake Pedal Position (Switch 2)

386

TM 9-2320-312-24-2

Troubleshooting Section

"Idle/PTO Bump rpm"

Note: If the vehicle is programmed to use the

Dedicated PTO, the PTO on/off switch overrides the

"Idle/PTO rpm Ramp Rate"

cruise control on/off switch. The PTO on/off switch

overrides the cruise control on/off switch when

"PTO Vehicle Speed Limit"

the vehicle speed is within the range of the "PTO

Vehicle Speed Limit" that is programmed.

"Cruise control pause switch"

Set/Resume Switch

The vehicle speed calibration can also affect the

With the cruise control on/off switch in the ON

cruise control, fast idle, the idle set speed, and the

position and the vehicle speed within the range of

PTO if the vehicle speed calibration is incorrectly

the programmed Low Cruise Control Speed Set

programmed. Refer to Troubleshooting, "Customer

Limit and the High Cruise Control Speed Set Limit,

Specified Parameters".

momentarily pressing the set switch will activate

cruise control and the ECM will maintain the current

Service Brake Pedal Position (Switch 2)

speed.

The switch for the service brake pedal position

After a speed has been set and the speed is then

(switch 2) is normally open when the respective

disengaged by using the brake, the clutch, the

pedal is released. Depressing the brake pedal

cruise control pause switch, or the on/off switch,

should close the individual circuit. This switch is

the ECM will seek the previous set speed when the

OEM supplied. The service brake pedal position

resume switch is toggled. This assumes that the

(switch 2) is typically a pressure switch.

vehicle speed is above the "Low Cruise Control Set

Speed Limit" for cruise control or the vehicle speed

The following background information is related

is below the "Idle/PTO Vehicle Speed Limit" for the

to this procedure:

idle and the PTO.

The kickout switch refers to the switch that is used

After a speed has been set, pressing and holding

to exit the cruise control, the PTO, fast idle, or the

the set/resume switch in position will cause the

idle set speed.

engine to establish a new set speed. The system's

reaction depends on the programming of the

The operation of the Caterpillar electronic engine

"Cruise/Idle/PTO Switch Configuration".

cruise control is similar to the operation of the

cruise controls that are installed in automobiles. The

When the set/resume switch is momentarily pressed,

operation of fast idle, idle, and PTO are similar to

the cruise set point will change one mph. The

the operation of cruise except that the Idle and the

rate of change is dependent on the programmed

PTO govern engine rpm instead of vehicle speed.

"Idle/PTO Bump rpm" when an idle speed is set.

Note: Idle in this procedure is an engine idle rpm

above the programmed low idle rpm. Idle is set

Cruise Control Pause Switch

by using the Cruise Control On/Off switch and

The cruise control pause switch is not a switch

the Set/Resume switch. Refer to Troubleshooting,

that is wired to an input. The switch position is

"PTO Switch Circuit - Test" for additional information

broadcast over a J1939 data link. The parameter

regarding the programmable options for the

"Cruise Pause Switch" must be programmed to

Dedicated PTO.

use a cruise control pause switch. After a speed

has been set and the speed is then disengaged

Note: Fast idle in this procedure is an engine idle

by using the cruise control pause switch, the ECM

rpm above the programmed low idle rpm. Fast idle

will seek the previous set speed when the resume

is set by using a dedicated fast idle switch.

switch is toggled. This assumes that the vehicle

speed is above the "Low Cruise Control Speed

Cruise Control On/Off Switch

Set Limit" for cruise control or the vehicle speed is

below the "Idle/PTO Vehicle Speed Limit" for the

This switch must be ON before cruise control or

idle and the PTO.

controlled idle can be activated. This switch is

ON when the switch is closed. When the switch is

closed the following terminals are connected:

Kickout Switches

ECM connector J1/P1 terminal 59 (cruise control

on/off switch)

Terminal 5 (AP sensor/switch sensor common)