C13 and C15 Engines for Combat and Tactical Vehicles Caterpillar

"Lower Gears Engine RPM Limit"

The engine will accelerate at a slower rate when this limit is exceeded under normal driving conditions. This parameter is used to encourage the driver to shift to the next highest gear.

"Lower Gears Turn Off Speed"

The "Lower Gears Turn Off Speed" parameter is the vehicle speed which turns off the "Lower Gears Engine RPM Limit". This must be matched with the "Lower Gears Engine RPM Limit" to the specific drive train for best performance.

"Intermediate Gears Engine RPM Limit"

This parameter is similar to the "Lower Gears Engine RPM Limit". The engine will accelerate at a slower rate when this limit is exceeded under normal driving conditions. This parameter is typically programmed to a slightly higher rpm than the "Lower Gears Engine RPM Limit".

"Intermediate Gears Turn Off Speed"

This parameter is similar to the "Lower Gears Turn Off Speed". This parameter is typically programmed to a slightly higher vehicle speed than the "Lower Gears Turn Off Speed".

"Gear Down Protection RPM Limit"

This parameter is the engine rpm limit when the vehicle speed is above the "Gear Down Protection Turn On Speed". This is a hard limit. The Engine Control Module (ECM) will not allow fuel to the engine above this limit. This parameter is used to encourage the driver to shift into overdrive or top gear.

"Gear Down Protection Turn On Speed"

This parameter is the vehicle speed when the "Gear Down Protection RPM Limit" is turned on. This must be matched to the specific drive train for best performance. Above this vehicle speed limit, the engine rpm will be limited by the "Gear Down Protection RPM Limit".

"Low Idle Engine RPM"

The "Low Idle Engine RPM" is the minimum engine rpm.

"Transmission Style"

This parameter indicates the type of transmission configuration that is installed in the vehicle to the ECM. This parameter is used by the ECM to read the signals from the following devices:

• Brake switch (No. 2)

• Clutch switch

• Neutral switch

If an automatic transmission is installed, program this parameter to one of the following options:

• Automatic option 1

• Automatic option 2

• Automatic option 3

• Automatic option 4

The manual selection requires a clutch pedal position switch to be connected to the ECM connector J1/P1:24. The transmission selections with a neutral switch require a transmission neutral switch to be connected to the ECM connector J1/P1:62. J1/P1:62 is the input 12. The transmission selections with two brake switches require a second brake switch to be connected to the ECM connector J1/P1:64. J1/P1:64 is the input 13.

The Eaton Top 2 transmission is a manual transmission and the Eaton Top 2 transmission requires a clutch switch. The ECM operates two outputs in order to control shifting between the top two gears of an Eaton Top 2 transmission. A total of four parameters must be programmed for the system to operate correctly.

"Eaton Top 2 Override with Cruise Switch"

If this parameter is programmed to "Yes" the cruise control On/Off switch can be used to disable Top 2 mode. If the cruise control On/Off switch is turned to the OFF position and the transmission is not in Top 2 mode, the Top 2 mode will be disabled. This condition is applicable to the manual mode of operation only. If the cruise control On/Off switch is turned to the ON position, the Top 2 mode will be enabled and the transmission will be allowed to shift automatically in the Top 2 gears. When the vehicle is operating in one of the Top 2 gears and the Top 2 mode is enabled, switching the cruise control On/Off switch to the OFF position will place the transmission in hold mode. When the transmission is in the hold mode, the transmission will not shift out of the currently selected gear. When the cruise control On/Off switch is returned to the ON position, the transmission will return to Top 2 mode. When the clutch is depressed and the transmission is in the hold mode, the manual mode will be enabled and the Top 2 will be disabled.

"Top Gear Ratio"

The "Top Gear Ratio" identifies the highest gear ratio for an Eaton Top 2 transmission. For example, tenth gear for an Eaton Super 10 Top 2 transmission is the top gear. The programmable range is 0.000 to 3.750 in 0.001 increments. The default is 0.000. Refer to ""Gear Ratios for Eaton Top 2 Transmission"" for programmable values for each Eaton Top 2 transmission.

Note: This parameter must be precisely programmed to three decimal places to ensure the proper operation of the Eaton Top 2 and Caterpillar engine drive train in the top two gears.

"Top Gear Minus One Ratio"

The "Top Gear Minus One Ratio" identifies the second highest gear ratio for an Eaton Top 2 transmission. For example, ninth gear for an Eaton Super 10 Top 2 transmission is top gear minus one. The programmable range is 0.000 to 3.750 in 0.001 increments. The default is 0.000. Refer to ""Gear Ratios for Eaton Top 2 Transmission"" for programmable values for each Eaton Top 2 transmission.

Note: This parameter must be precisely programmed to three decimal places to ensure the proper operation of the Eaton Top 2 and Caterpillar engine drive train in the top two gears.

"Top Gear Minus Two Ratio"

The "Top Gear Minus Two Ratio" identifies the third highest gear ratio for an Eaton Top 2 transmission. For example, eighth gear for an Eaton Super 10 Top 2 transmission is top gear minus two. The programmable range is 0.000 to 3.750 in 0.001 increments. The default is 0.000. Refer to ""Gear Ratios for Eaton Top 2 Transmission"" for programmable values for each Eaton Top 2 transmission.

Note: This parameter must be precisely programmed to three decimal places to ensure the proper operation of the Eaton Top 2 and Caterpillar engine drive train in the top two gears.

"Gear Ratios for Eaton Top 2 Transmission"

Note: The XX that appears in the model number of the transmission refers to the nominal torque capacity. XX times 100 equals the nominal torque capacity. For example, RTLO-14613A has a nominal torque capacity of 14 times 100 or 1900 N·m (1400 lb ft).

The model designation of the transmission and other information are stamped on a tag on the transmission. The tag is located on the lower left side near the front of the transmission.

"Default Torque Limit Master Source Address"

Configurable Default Torque Limit (CDTL) Feature:

• The CDTL feature is available for EPA-Exempt C13 engines for Combat and Tactical Vehicles serial number prefix RLG. This feature is not currently available on earlier C13 engines with serial number prefixes:PRM, EMS and EMF.

• The base software does not support the Allison^® transmission "Low Range Torque Protection" feature.

The CDTL feature allows a selectable drivetrain or other vehicle module to electronically limit the engine torque in two different ways depending on the current condition of the SAE J1939 data link. The selected vehicle module must communicate by SAE J1939 data link, and be compatible with the CDTL feature (must provide a torque limit value). In normal operation with a functioning SAE J1939 data link, the CDTL feature can trigger an engine derate via the "Engine Derate Switch" data link value from the programmable SAE J1939 Master Source Address of the selected vehicle module with a value of ON. In event of a data link failure, the engine will apply the same default torque limit. The engine and configured drivetrain module will have previously "agreed" to the torque limit via communication after key-on. Torque Limit values are in Nm.

The engine's initial un-configured (not enabled) Default Torque Limit (DTL) value will not provide torque limiting prior to receiving a desired DTL value from the selected module. This is indicated on the J1939 data link with a "not available" (0xFFFF) value broadcast for SPN 1846 within the EC1 engine configuration message. Once enabled, the last received DTL value for the currently selected module (Master module) will be indicated by this data value.

The selected module (the Master module) must broadcast its Default Torque Limit (DTL) SPN to communicate its desired DTL value that the engine will use in the event of a J1939 data link failure. The engine will retain this DTL value even across a key cycle until a new DTL value is received from the programmed "Master" module or until the feature has been disabled by setting the configurable parameter to 0.

The DTL value from the selected module is stored in a non-volatile memory. To prevent an erroneously low "Default Torque Limit" value from completely disabling the vehicle, a Lower Boundary will apply to the torque limit, equal to 50 percent of the available torque at governed speed.

The engine and the selected module must maintain consistent communication to allow the CDTL strategy to function. If the engine has previously recognized a "Default Torque Limit" message from the selected module (i.e. CDTL is "armed") and subsequently loses communication with the vehicle module, the engine will be derated to not exceed the DTL value or the Lower Boundary, whichever is higher.

• If a selected vehicle module's J1939 Master Source Address is programmed, but the engine does not receive a DTL value from the module, torque limiting will not occur.

• If the engine has previously recognized a DTL torque value, and is subsequently removed for dyno testing or the ECU is swapped to another engine, the ECU continues to store the most recent DTL value and continues to limit torque, unless the feature is disabled by programing it to 0.

Illustration 15 shows the "Engine Derate Switch" input values from the selected module.

The CDTL feature is disabled when the parameter is programmed to 0. The CDTL feature is enabled by programming the parameter to the "Default Torque Limit Master J1939 Source Address" of the selected module.

Reference: SAE J1939 Industry Group 0 Global Preferred Addresses table for a complete list of J1939 Source Addresses for vehicle modules.

• 0 = Disabled (not programmed)

• 3 = SA 3 = Transmission

• 49 = SA 49 = Primary Cab Controller

"Governor Type"

This parameter determines the type of governor that controls the engine. Select "Full Range" for manual transmissions and for electronically shifted manual transmissions. Select "Min/Max" for automatic transmissions.

The "Min/Max with Speed Control" option allows the use of a full range governor when the vehicle is not moving and the transmission is in neutral. The "Min/Max with Speed Control" option is preferred for applications that currently use the "Min/Max" governor.