C9 Urban Transit Bus Engine Caterpillar

"PTO Configuration"

The "PTO Configuration" determines the features that are available for dedicated PTO applications and the input signals that are used for dedicated PTO applications. When the "PTO Configuration" is programmed to "Off", the application does not use the settings for the PTO. The remaining programmable options for the PTO require a PTO on/off circuit that is connected to ECM input 1 (ECM connector J1/P1:56). A PTO switch on lamp can also be connected to output 1 (ECM J1/P1 terminal 30).

If the parameter "PTO Configuration" is programmed to the "Cab Switches", the ECM will use the signals from the following two switches for PTO control and cruise control:

• Cab set switch (J1/P1 terminal 35)

• Resume switch (J1/P1 terminal 44)

If the parameter "PTO Configuration" is programmed to "Remote Switches", the ECM will monitor programmed signals such as the remote set switch and remote resume switch. Signals from the cab controls will be ignored when the PTO on/off circuit is on. The following components are cab controls:

• Brake switch

• Clutch switch

• Accelerator

• Cruise control switches

If the parameter "PTO Configuration" is programmed to "Remote Throttle", the ECM will monitor input 8 (J1/P1:68) for the remote accelerator pedal. The ECM will monitor programmed signals and the ECM will ignore all cab controls when the PTO on/off circuit is on.

"PTO Top Engine Limit"

The "PTO Top Engine Limit" is the top engine limit that is available with a PTO on/off circuit that is connected to input 1 (J1/P1:56).

Note: The "PTO Configuration" must be programmed to "Cab Switches", to "Remote Switches", or to "Remote Throttle" before this parameter can be programmed.

"PTO Engine RPM Set Speed"

The "PTO Engine RPM Set Speed" is the engine rpm that is allowed by the ECM when the PTO on/off circuit is on and the set switch is actuated.

If the "PTO to Set Speed" parameter is programmed to "Yes", the engine will proceed to this speed whenever the PTO on/off circuit is turned on.

Note: "PTO Configuration" must be programmed to "Cab Switches" or to "Remote Switches" for this parameter to function.

This parameter must be programmed higher than the programmed low idle. If the "PTO to Set Speed" is programmed to a higher value than the "PTO Top Engine Limit", the set speed will be limited by the lower "PTO Top Engine Limit".

For one rpm set speed above low idle, program the "PTO Top Engine Limit" to the same rpm as the "PTO Engine RPM Set Speed".

For two rpm set speeds above low idle, program this parameter to some intermediate value between the low idle and the "PTO Top Engine Limit".

Place the PTO on/off switch to the ON position. Toggle the set switch once in order to cause the rpm to advance to the "PTO Engine RPM Set Speed". Toggle the set switch again in order to increase the engine rpm to the "PTO Top Engine Limit". Toggling the resume switch decreases the engine rpm to the previous set speed.

"PTO Engine RPM Set Speed Input A"

If the "PTO Engine RPM Set Speed A" parameter is programmed to the corresponding switch input option, the switch is used in order to control engine speed during PTO operation. The "PTO Configuration" parameter must be programmed to "Cab Switches", to "Remote Switches", or to "Remote Throttle" and the "PTO Engine RPM Set Speed A" parameter must be programmed to a valid speed.

"PTO Engine RPM Set Speed Input B"

If the "PTO Engine RPM Set Speed B" parameter is programmed to the corresponding switch input option, the switch is used in order to control engine speed during PTO operation. The "PTO Configuration" parameter must be programmed to "Cab Switches", to "Remote Switches", or to "Remote Throttle" and the "PTO Engine RPM Set Speed B" parameter must be programmed to a valid speed.

"PTO to Set Speed"

This parameter causes the ECM to proceed to the programmed "PTO Engine RPM Set Speed" when the PTO on/off switch is on. "PTO Configuration" must be programmed to "Cab Switches" or to "Remote Switches" before this parameter can be programmed.

Note: This parameter is not available when "PTO Configuration" is programmed to "Remote Throttle".

"Maximum PTO Enable Speed"

This parameter specifies the maximum engine speed for the engagement of the PTO mode. The PTO mode will engage when the engine rpm is equal to the programmed limit or less than the programmed limit.

"PTO Cab Throttle RPM Limit"

This determines the engine rpm limit of the pedal position sensor for the cab accelerator and cab set/resume switch when "PTO Configuration" is programmed to "Cab Switches" and the PTO on/off circuit is ON. This parameter is intended to prevent engine overspeed when the dedicated PTO is used.

• If the parameter is programmed to "Low Idle", the cab controls are ignored.

• If the parameter is programmed to "Top Engine Limit" (TEL), the engine will operate to the programmed "Top Engine Limit".

• If the parameter is programmed to "PTO Top Engine Limit", the engine will operate to the programmed "PTO Top Engine Limit".

Note: "PTO Configuration" must be programmed to "Cab Switches" for this parameter to take effect. If "PTO Configuration" is programmed to "Remote Switches" or to "Remote Throttle", the ECM will always ignore the cab controls when the PTO on/off circuit is on.

"PTO Kickout Vehicle Speed Limit "

This is the maximum vehicle speed for setting or maintaining a set engine rpm in PTO mode. PTO mode is entered if the PTO on/off switch is on. (This uses input 1.) If the vehicle speed signal exceeds this value, the engine will not maintain the set engine rpm.

"Maximum PTO Vehicle Speed"

This parameter specifies the maximum vehicle speed that is allowed when PTO mode is active. The engine will be derated in order to maintain this vehicle speed when the PTO mode is active.

"Torque Limit"

Illustration 1	g00628600
Operation of Torque limit (1) Programmed torque limit

The parameter for the "Torque Limit" defines the maximum torque output of the engine during dedicated PTO operation. This parameter provides temporary protection of equipment. The "Torque Limit" of the engine is active when the circuit for the torque limit switch is on. The maximum value is the rated torque of the engine. The "Torque Limit" is programmable to N·m (lb ft) of torque. Programming a value higher than the rated torque is limited by the ECM to rated torque. The torque limit is indicated by the dashed line in Illustration 1.

"PTO Shutdown Time"

The "PTO Shutdown Time" is the time (minutes) of engine operation with the PTO on/off circuit ON and no vehicle speed before shutting down. The timer will only count with no vehicle speed and the PTO on/off circuit turned on. The PTO shutdown timer will not begin counting if the engine is in cold mode. This parameter requires the "PTO Configuration" to be programmed to "Cab Switches", to "Remote Switches", or to "Remote Throttle" for the timer to function.

Note: This feature does not shut down the vehicle's power. The ECM and the vehicle remain powered.

"PTO Activates Cooling Fan"

This parameter requires the use of the ECM cooling fan circuit. When this parameter is programmed to "Continuous", the ECM will signal the cooling fan to run continuously when the PTO on/off circuit is on. The cooling fan runs continuously in order to reduce changes in the load while the engine is being used for dedicated PTO applications. When this parameter is programmed to "Normal", the PTO on/off circuit does not affect the cooling fan. In this mode, the operation of the fan is based on coolant temperature, on inlet air temperature or on air conditioning high head pressure. The "PTO Configuration" must be programmed to "Cab Switches", to "Remote Switches", or to "Remote Throttle" before this parameter can be programmed. The "Fan Control Type" must be programmed to "On/Off".

Note: If "Fan Control Type" is programmed to "On/Off" or to "Variable Speed Fan Option S" the transmission may cause the fan to turn ON via the J1939 Data Link. The transmission will turn the cooling fan ON if the temperature of the transmission oil is too hot.