chapter 5
reapply
(BPMV stage) opens inlet valve
dump
(BPMV stage) opens outlet valve
isolation
(BPMV) first stage of operation
f
T/F The power-up self-test occurs once the vehicle is shifted into drive or reverse.
a
Technician A says that the booster pump and accumulator take the place of a power booster in an integral system. Technician B says that a non-integral system can reach pressures of up to 2700 psi. Which technician is correct?
four-channel ABS
The control module of a ________ handles all four wheels separately.
prevent wheel lock-up
The function of an ABS system is to _______.
high pressure accumulator
The pressure sensor continuously reads ________ ___________ ___________ pressure.
EBCM
The solenoid valve block is part of the ______.
the pressure sensor tells the EBCM to turn it on so it can stabilize pressure
What tells the pump to turn on ?
isolation
contains one supply valve for each driven wheel(ONE OF THESE NOT RIGHT)
booster pump
converts mechanical force to hydraulic pressure
power up self test
what applies power to the ABS pump and relays when the ignition is engaged?
dual stage solenoid valve
what combines a isolation and a dump valve?(ONE OF THESE NOT RIGHT)
electronic brake control module
what monitors brake system by receiving and sending information from and to related components and systems ?
the solenoid block
what part of the braking system is attached to a circuit board and houses many solenoids?
eccentric pump
what rotates, causing the pump elements to move in and out?
EBCM
what's monitoring the pump that is holding pressure inside the accumulator ?
electronic control module
where does input from various vehicle sensors such as the wheel speed sensor go ?
The EBCM talks to the PCM because it needs to know that the car is running so the ABS will be active. This "varying voltage" would come from the engine turning over but not starting ch ch ch ch ch ch
where would varying electrical voltage come from that would not allow the ABS system to work
pump pressure switch
which sensor monitors pressure in the accumulator? in this the EBCM will signal the pump to restore pressure.
one channel is just for the rear wheels and the ABS helps control both during slippage
which wheels would a one channel ABS braking apply
So it can provide power to the rest of the ABS, motor and solenoid valves
why would the EBCM signal the relay (relay switch) to close?
output
The ABS warning light belongs in which category? input or output
electronic brake control module
The Bosch 8.0 uses the _______ __________ _________ as the communication and monitoring system.
traction control system
allows the pressure from the wheel brake to dissipate back to the accumulator(ONE OF THESE NOT RIGHT)
solenoid block
provides the electromagnetic signal to engage each of the valves individually in this assembly
pump motor
provides the mechanical force to create hydraulic pressure
dump
returns valves to normal position, allowing hydraulic pressure to flow freely throughout the system (ONE OF THESE NOT RIGHT)
electromagnetic
solenoids operate using what type of force?
reapply
stage of operation that cuts off the pressure to the wheel brake(ONE OF THESE NOT RIGHT)
reapply
(BPMV stage) allows pressure to flow to hydraulic circuit
dump
(BPMV stage) directs pressure to accumulators
isolation
(BPMV stage) maintains pressure existing in hydraulic circuit
a four channel system
A fully independent suspension system would be installed on a vehicle with which type of ABS channel system?
REAR
Dual-stage solenoid valves are typically found on ______-wheel drive vehicles.
three
Front wheel drive and rear wheel drive might have a _________ channel ABS system
The high pressure uses a nitrogen charge. and the low pressure one contains a sealed piston
How does the low pressure and high pressure accumulator work?
The control module selects the lowest wheel speed to determine brake fluid pressure
How would a three channel brake system determine how to distribute brake fluid pressure?
solenoids
In an ABS system, the _______ rapidly open and close hydraulic valves.
three-channel ABS
On a front wheel drive vehicle, the control module of a ________ handles front wheels separately and the rear wheels as a pair.
one-channel ABS
On rear-wheel drive vehicles with a ________ system, the front wheels do not require speed sensors.
T
T/F A 3-channel ABS combines the two rear wheels under one valve set control.
T
T/F Accumulator high pressure is around 2700 psi.
F
T/F Accumulators store vacuum.
T
T/F In a low pressure system, the DC motor turns a shaft with an eccentric cam that forces pistons to pump fluid.
T
T/F Inlet valves remain open during normal operating conditions
T
T/F The Bosch 8.0 system integrates ABS, stability and traction control, and brake assist.
T
T/F The Bosch 8.0 system provides dynamic rear brake proportioning.
F
T/F The EBCM only communicates with vehicle sensors for its inputs.
F
T/F The brake modulator valve cuts off hydraulic pressure to the wheels for the duration of an ABS event.
T
T/F The electronic brake control module is considered the brain of the system.
T
T/F The motor turns on and off when it receives direction from the EBCM
F
T/F VSES and TCS use only the inlet and outlet valves in a 4-channel ABS.
b
Technician A says that the PCM provides the direction to all of the ABS outputs. Technician B says on modern vehicles the EBCM communicates with other modules and provides diagnostic information to the scan tool. Which technician is correct?
without driver control
The ABS pump creates hydraulic pressure ___________
PCM and TCM (transmission control module)
The EBCM is going to communicate with the ___ and the ___ to initialize and monitor ABS, TCS (traction) and VSES (stability)
ABS indicator
The ________ ______________ is on when a fault is detected in the system.
control module
The ________ may be called EBCM or CAB.
keep alive
The _________ _________ pump runs continuously when the ABS is functioning
The brake assist system
The _____________ _______ ____________ uses the ECBM and the vacuum power booster to increase braking force
input
The brake fluid sensor belongs in which category? input or output info?
input
The engine crank sensor belongs in which category? input or output?
yaw sensor
The lateral vehicle sway on turns is measured by the _______.
One Channel, three channel, and four channel.
The type of ABS
False
Traction control systems work best in deep snow and mud.
one channel ABS system
Type of ABS channel that control braking on rear wheels and has the wheel speed sensor on the transmission of differential Called RWAL by GM and RABS by ford
electronic brake control module
What component sends the command to the pump motor to turn on and off to create hydraulic pressure?
Fluid flows from master cylinder to the inlet valves then to the brakes. This valve control pressure to specific wheels. These valves can restrict lines if needed
What do the inlet valves do ?
The type of ABS system
What do the number of outlet valves depend on ?
Bleeds pressure from specific wheels when open so it equalize the system
What do the outlet valves do?
electronic brake control module
What does EBCM stand for ?
The type of ABS system
What does the number of inlet valves depend on ?
EBCM
What is going to monitor proper relay function and also reports its findings to other modules to ensure smooth sailing. like a short or open.
You'd find that on an older model car that's rear wheel drive ABS vehicles. It is a single solenoid that control both isolation and dump valves
When would you find a dual stage solenoid valve and what is that ?
exist really only for TCS and VSES features (Traction control and Vehicle stability). The number of valves depends on number of driven wheels. The position of the supply valves is usually closed but opens during traction control or stability type event to allow fluid into the pump
When would you find supply valves and what would the number of supply valves depend on ?
low pressure accumulator
Where does residual hydraulic pressure go when it is released from the wheel brake in a non-integral system?
accumulator
Which component of the brake pressure modulator valve stores pressurized hydraulic fluid?
isolation
Which valves in the brake pressure modulator valve are only used with the traction control system?
The outlet and supply valves ( the middle two) are normally closed until acted upon, and the inlet and isolation valves are usually open.
Which valves in the valve solenoid block are usually open and which ones are usually closed?
Exists for TCS and VSES as well. And the number of valves depends on the number of driven wheels. The position is usually in the open position and closes to maintain and build pressure in the pump.
Why do Isolation valves exist? What does the number of valves depend on?
for non integral system it would turn the pump on to make sure that enough fluid is pumped back into master cylinder. For integral system it would turn on the pump to ensure proper pressure in the accumulator.
Why would the EBCM tell the pump to turn on? why for integral system and why for non integral system ?
4-channel ABS
contains one inlet and outlet valve for each driven wheel(ONE OF THESE NOT RIGHT)
The EBCM will tell the PCM to retard the engine timing and reduce fuel injector pulse width.
during a TCS (traction control) even the EBCM will talk to the PCM why?
the EBCM figures out what needs to be opened or closed and then sends an electrical current to the coil which engages the solenoid.
how is solenoid open or closed?
four wheel speed sensors
how many wheel speed sensors does a front wheel drive vehicle have with a three channel ABS system?
the outlet valve will open
in a non integral system where does pressure come from to get to the accumulators?
A dual stage solenoid valve
in this valve you could have isolation, dump and reapply stages. (ONE OF THESE NOT RIGHT)
brake assist system
provides greater vacuum to the power booster to increase braking force
plunger pump
provides hydraulic pressure to one side of the vehicle or the other
electromagnetic device that moves a valve
provides the electromagnetic charge to move a valve(ONE OF THESE NOT RIGHT)
dual-stage solenoid valve
uses one solenoid to control both the isolation and dump valve(ONE OF THESE NOT RIGHT)
plunger pumps
what are the things that go on each side of the valve block? They send pressure to the pair of wheels associated with its side of the pump
traction control switch
what disables system on driver command for driving in deep snow or mud?
Brake pressure modulator valve
what does BPMV stand for
vehicle stability enhancement
what helps maintain vehicle contact with the road during understeer or oversteer conditions?
ABS indicator
what is an icon on the dashboard that stays illuminated when a fault is present?
EBCM
what is constantly monitoring the wheel speed sensor to detect problems or slippage? ... it's the only thing always monitoring the wheels speed sensor
the valve that the fluid flows through to get to the brakes
what is the dump valve?
it creates the hydraulic pressure for the ABS system. It's in between two pistons in the booster pump.
what is the eccentric cam?