Brake and Traction Telltales
Telltales and messages appear on the driver display. The positions of the telltales vary, but most use standard symbols.
The colors of telltales indicate the hazard level as follows: red (warning), amber (caution), green (normal function), blue (active status), grey (passive status), white (informational).
The colors of messages indicate the hazard level as follows: red (warning), amber (caution), grey (informational).
Telltales for braking and traction related features are listed in Table . Every vehicle may not be equipped with every feature.
Table 1, Braking and Traction Telltale Lamps
|
Telltale Lamp |
Color |
Description |
Related Information |
|
|---|---|---|---|---|
 |
Green |
Recuperative Braking |
Indicates recuperative braking has been activated by moving the right-hand stalk switch into position 1, 2, or 3 (low, medium, or high). |
A blue line appears on the charge portion of the power gauge showing the amount of available recuperative braking requested. |
 |
Green |
Descent Control Mode |
Indicates descent control mode is active. |
The driver should always be ready to intervene by applying the service brakes. On steep roads recuperative braking may not be able to maintain the vehicle set speed. |
 |
Amber |
Hill Start Aid Disengaged |
A blinking telltale indicates hill start aid is off. A solid telltale indicates a fault with the system. |
To turn on HSA, press the HSA OFF switch again or cycle the vehicle keyswitch. |
 |
Grey |
Brake Hold Mode Engaged |
Indicates brake hold mode is active. The service brake is maintained when the driver takes their foot off the brake pedal. |
To release the brake hold, press the accelerator pedal, engage the park brake, or rapidly apply and release the brake pedal. |
 |
Red |
Park Brake Engaged |
Indicates the park brake is engaged. |
Always engage the park brake before exiting the vehicle. |
 |
Red |
Low Brake Air Pressure |
Indicates air pressure in the primary or secondary reservoir has dropped below approximately 70 psi (483 kPa). Bring the vehicle to a safe stop and have the air system repaired before continuing. |
A buzzer sounds if the park brake is released or the vehicle is moving when the air pressure is below 70 psi. |
 |
Amber |
Tractor Antilock Brake System (ABS) |
Momentary illumination indicates the vehicle ABS is engaged. Solid illumination indicates a problem with the vehicle ABS. Repair the ABS to ensure full braking capability. |
Even if the ABS is completely inoperative, normal braking ability is maintained. |
 |
Amber |
Trailer Antilock Brake System (ABS) |
The telltale will not illuminate if an incompatible trailer is connected to the tractor. Momentary illumination indicates the trailer ABS is engaged. If the telltale lamp illuminates momentarily during vehicle operation, then shuts off, a fault was detected and corrected. Solid illumination indicates a problem with the trailer ABS. Repair the trailer ABS immediately to ensure full braking capability. |
N/A |
 |
Amber |
Automatic Traction Control (ATC) Active |
A flashing telltale lamp indicates a wheel spin event has been detected, and the ATC system is active. |
N/A |
 |
Amber |
Automatic Traction Control (ATC) Deactivated |
Indicates the ATC SPIN switch has been pressed to allow wheel slip. |
Press the switch again to active ATC. |
 |
Red |
Brake System Warning |
A solid telltale indicates a failure in the Antilock Braking System/Electronic Braking System (ABS/EBS) or the electronic air processing unit (EAPU). Stop the vehicle and call for service. |
N/A |