ABS
The purpose of the antilock brake system (ABS) is to prevent wheel lockup under braking conditions on
virtually any type of road surface. Antilock braking is desirable because a vehicle that is stopped without
locking the wheels retains directional stability and some steering capability. This allows the driver to retain
greater control of the vehicle during braking.
ELECTRONIC STABILITY PROGRAM (ESP)
The ESP system enhances directional control and stability of the vehicle under various driving conditions. ESP
corrects for over/under steering of the vehicle by applying the brake of the appropriate wheel to assist in
counteracting the over/under steer condition. Engine power may also be reduced to help the vehicle maintain
the desired path. ESP uses sensors in the vehicle to determine the vehicle path intended by the driver and
compares it to the actual path of the vehicle. When the actual path does not match the intended path, ESP
applies the brake of the appropriate wheel to assist in counteracting the oversteer or understeer condition
Oversteer - when the vehicle is turning more than appropriate for the steering wheel position.
Understeer - when the vehicle is turning less than appropriate for the steering wheel position.
The "ESP/TCS Indicator Light" located in the instrument cluster, starts to flash as soon as the tires lose traction
and the ESP system becomes active. The "ESP/TCS Indicator Light" also flashes when TCS is active.
BRAKE ASSIST SYSTEM (BAS)
The BAS is designed to optimize the vehicle's braking capability during emergency braking maneuvers. The
system detects an emergency braking situation by sensing the rate and amount of brake application and then
applies optimum pressure to the brakes. This can help reduce braking distances. The BAS complements the
antilock brake system (ABS). Applying the brakes very quickly results in the best BAS assistance.
ELECTRONIC VARIABLE BRAKE PROPORTIONING
Vehicles equipped with ABS use EVBP to balance front-to-rear braking. The EVBP is used in place of a rear
brake proportioning valve. The EVBP system controls the slip of the rear wheels during braking at low to
moderate deceleration, up until the point where ABS control is necessary. The brake pressure at the rear wheels
is controlled by using the inlet and outlet valves located in the hydraulic control unit (HCU).
EVBP activation should not be perceptible by the customer because there is no pump motor noise and almost no
brake pedal feedback.
OPERATION
ANTILOCK BRAKE SYSTEM (ABS)
There are a few performance characteristics of the MK25e anti-lock brake system that may, at first, seem
abnormal but in fact are normal. These characteristics are described below.
NORMAL BRAKING
2007 Dodge Nitro R/T
2007 BRAKES ABS Service Information - Nitro