Cold Mode Operation

TM 9-2320-312-24-2

Troubleshooting Section

"Vehicle Speed Limit"

If the fuel position is equal to the rated fuel limit

and the fuel position is less than the FRC limit,

"Lower Gears Engine RPM Limit"

the electronics are operating correctly. Proceed

to "Vehicle Speed Signal".

"Intermediate Gears Engine RPM Limit"

3. If the fuel position is not equal to the rated fuel

"Gear Down Protection Engine RPM Limit"

limit and/or the fuel position is not less than the

FRC limit, perform the following tests in order:

5. Set each parameter to the parameter's maximum

4. When the engine is off, turn the ignition key

value one at a time and determine whether the

switch to the ON position. Check the boost

problem is corrected.

pressure on the electronic service tool status

screen.

Cold Mode Operation

When the engine is off, the boost pressure

Note: This is normal operation if the problem occurs

should be 0 kPa (0 psi).

only after start-up in cold weather.

Accelerator Pedal Position

1. Connect the electronic service tool to the cab

data link connector.

1. Connect the electronic service tool to the cab

2. Monitor the electronic service tool in order to

data link connector.

verify that the engine has progressed from cold

mode.

2. Monitor the status of the accelerator pedal

position sensor. Operate the engine at high idle

An active cold mode is indicated in the upper

with the vehicle in neutral.

corner of any status screen.

If the engine can not reach the programmed

top engine limit, check the duty cycle of the

Torque Limit Switch

accelerator pedal position sensor in order to

ensure that the duty cycle of the accelerator

1. Connect the electronic service tool to the cab

pedal position sensor is within calibration (75 to

data link connector.

90 percent at high idle).

2. Check the setting for the Customer Parameter

If the accelerator pedal position is unstable,

for the "Torque Limit".

check the duty cycle of the accelerator pedal

position sensor. Check the duty cycle of the

If the "Torque Limit" is programmed below

accelerator pedal position sensor by slowly

2712 Nm (2000 lb ft), check the status screen

operating the accelerator pedal in order to verify

for the torque limit switch. Ensure that the status

that the accelerator pedal position sensor is

screen indicates that the torque limit switch is

within calibration. The accelerator pedal position

off. If the status of the torque limit switch is

sensor is within calibration when both of the

on and a "Torque Limit" is programmed, the

following conditions are met:

system is operating correctly. If the switch that is

connected to this signal input is not switching on

10 to 22 percent at low idle

and switching off, refer to Troubleshooting, "PTO

Switch Circuit - Test".

75 to 90 percent at high idle

Electronic System

Also, ensure that the duty cycle changes as the

pedal position changes.

1. Connect the electronic service tool to the cab

data link connector.

If a problem with the accelerator pedal position

sensor is suspected, refer to Troubleshooting,

2. Monitor the Fuel Position, the Rated Fuel Limit

"Accelerator Pedal (Throttle) Position Sensor

and the Fuel Limit for the Fuel Ratio Control

Circuit - Test".

(FRC).

Vehicle Speed Signal

While the vehicle is operating under full load, the

parameters should meet the following conditions:

Monitor the vehicle speed signal. Ensure the

accuracy of the vehicle speed signal by comparing

The fuel position is equal to the rated fuel limit.

the vehicle speed signal to the actual vehicle speed.

The fuel position is less than the FRC limit.