Chapter 5 Flashcards
Explain why 100% copper line should never be used as brake lines.
- 100% copper line should never be used for brake lines because it cannot withstand the pressure or vibrations
- Describe an ISO flare.
- An iso flare uses a bubble shaped end formed on the tubing to create a better seal with less torque
- Why are brake hoses marked with raised ribs or
colored stripes?
- Used to identify if twisting has occurred during installation that could lead to rupture
- Describe how an internal brake hose problem can
cause brake pull and/or brake drag.
- When a brake line wears to the point that a flap of rubber breaks off the wall and impedes flow either from the master cylinder to the wheel(pulling) or from the wheel back to the master cylinder(drag)
- Describe how a leak-free fitting is achieved with
SAE flare fittings.
- The male and female connectors are flared at 45° and 42° respectively, the 3° mismatch causes an interference fit that creates a leak-free seal
- Describe why a double flare is a better choice
than a single flare.
- The double flare has more sealing power and is more resistant to cracking than the single end flare
Explain how the ABS system has taken the place
of many of the hydraulic control valves.
- The ABS system uses hydraulic valves to prevent wheel lockup. Therefor the vehicles movements are predictable, and the old valves can be replaced by electronically controlled valves
- Describe the electronic brake pad wear indicator
system used on some vehicles
- The electronic brake pad wear indicator system uses a pellet attached to ground in the wear material. When the brake pads wear to a pre-determined point the circuit opens and the warning light comes on
- Explain the operation of the BPP sensor.
- The BPP sensor tells the BCM to turn on the brake lamps as well as how fast and how hard the brakes were applied for traction control
- Describe an ISO fitting.
- A type of tubing flare connection in which a bubble-shaped end is formed on the tubing; also called a bubble flare
Brake lines or tubing consist of _______________tubes or pipes and flexible _______________ connected with fittings.
Steel/Hoses
There are two common types of flares formed on the end of brake tubing, the _______________ flare and the _______________ flare.
double/iso
SAE Standard J1047 requires that an 18-inch length of tubing must withstand an internal pres- sure of _______________ psi.
8000
. An ISO flare is not _______________ on itself as is a double flare.
folded
. _______________ fittings have become popular with both domestic and foreign vehicle manufacturers.
iso
Straight ______________________________ fit- tings are usually found on the ends of brake hoses that attach to calipers or wheel cylinders.
compressed washer
A ______________________________ is used to attach a hose or tube to a port on a cylinder or caliper at a close right angle
banjo
Late-model vehicles use a _______________ _______________ position sensor in place of brake lamp switches.
break pedal
The brake lamps, turn signals, and hazard flash- ers on many late-model vehicles are operated by a _______________ _______________ connected to the computer network.
lighting module
The _______________ _______________ switch has replaced the pressure differential valve warn- ing switch on most vehicles.
warning lamp
Technician A says that a 100 percent copper tube is often used as a brake line material. Technician B says there is a copper-nickel alloy brake tubing that meets SAE Standard J1047 and ISO 4038. Who is correct?
B only
Technician A says that a 100 percent copper tube is often used as a brake line material. Technician B says there is a copper-nickel alloy brake tubing that meets SAE Standard J1047 and ISO 4038. Who is correct?
B only
Technician A says fittings with an external taper is simply called a standard flare. Technician B says a fitting with an internal taper is called an inverted or LAP flare. Who is correct?
both
Technician A says that a metering valve delays the application of the rear drum brakes. Technician B says that the metering valve is only needed on four-wheel disc brake vehicles. Who is correct?
Neither
Technician A says on many vehicles the lighting module controls the brake lamps and turn signals. Technician B says that these vehicles use the turn signal switch as an input to the lighting module. Who is correct?
both
Technician A says that a proportioning valve pro- vides greater pressure to the rear drum brakes during normal vehicle load. Technician B says that a proportioning valve provides lower pres- sure to the front disc brakes during initial brake application. Who is correct?
neither
While discussing electrically actuated parking brakes, Technician A says these systems operate via electric actuators located on the rear brake calipers, or by electric cable actuators. Technician B says these actuators are controlled by their own control module. Who is correct?
both
Technician A says some vehicles use tubing sized in metric diameters. Technician B says some common metric diameters are 4.75 mm, 6 mm, 8 mm, and 10 mm. Who is correct?
both
While discussing mechanical brake lamp switches, Technician A says the stop-lamp switch is a normally open momentary contact switch. Technician B says the same circuit is used to alert the ABS to monitor wheel speed sensors during braking. Who is correct?
both
While discussing brake pad wear indicators, Technician A says that many brake pads utilize a simple scraper built into the brake pad itself that touches the rotor when the pads wear down. Technician B says the scraping sound goes away when the brakes are released. Who is correct?
A only
