Automatic Traction Control
Vehicles with electronic engines and ABS may have Automatic Traction Control (ATC). On these vehicles, the ATC system automatically limits wheel spin during reduced-traction situations. In normal braking applications, the standard air brake system is in effect.
If the vehicle has ATC, there will be a momentary-contact rocker switch on the dash labeled Deep Mud and Snow with an ATC icon. See Fig.. Pressing the switch will temporarily allow more drive wheel spin. Pressing the switch again will cycle the system back to normal operation.
Fig. 1, Deep Mud and Snow Switch
An additional solenoid valve is installed. During reduced-traction situations, the ATC solenoid valve controls air pressure to the modulator valves and they in turn increase, hold, or reduce pressure to the appropriate brake chambers to provide better traction whenever wheel spin occurs.
When the ATC system is in the NORMAL mode, it will apply gentle braking to the spinning wheel, to feed power to the wheel(s) with better traction. If both wheels are spinning, the system will signal the engine to reduce power.
Notice: The deep snow and mud option is intended to be used under specific slippery conditions that require momentary increased wheel spin. Using this option for an extended period of time may damage the vehicle brake system.
ATC includes a deep snow and mud option to increase available traction on extra soft surfaces like snow, mud, or gravel. The activation of the deep snow and mud option is indicated by a flashing WHEEL SPIN lamp.
After the ignition switch is turned on, the tractor ABS lamp and the WHEEL SPIN indicator lamp come on for about three seconds. After three seconds, the warning lights go out if all of the tractor's ABS components are working.
Important: If any of the ABS warning lights do not work as described above, or come on while driving, repair the ABS immediately to ensure full antilock braking capability.