Wiring Diagram Practice

There are a number of components in the ABS systems that are also used for injection. These are mostly speed sensors e.g. wheel speed and engine speed.

Using the wiring diagram in the workshop manuals identify the wheel speed sensors and the list their wire colours for each sensor.

Front Right : Black/White

Front Left : Green/Red

Rear Left : Blue/Pink

Rear Right : Yellow/Brown

On th ABS wheel sensor what is the reason for the braded wire?

So it can be used for shielding purposes or used alone in flattened form as a grounding strap.

Advantages of the Braded wire.

1. Power -Braded wire can carry more power because it has a higher surface area. Each braded wire presents all sides that would be smashed against the center of the solid wire. Braded wire is also used to carry large amounts of power because it is easier to dissipate the heat that so much flowing electricity generates when there is space between wires.



2. Sound - solid strand wires are capable of carrying extremely high frequencies. These frequencies can be disrupted by imperfections on the surface of the wire, so solid wires perform better because they have less surface area. The only difference in sound is caused by the tiny air pockets between wires.



3. Flexibility - Braded wire is used for devices that need to be compact because of its greater flexibility. Car batteries are one of the most common devices that require tightly packed copper wire.

Identify and list all the fuses that are used by the ABS circuit.

F14 fuse box, FL main, Y-G, Gauge 10A, Dome 20A, STOP 15A (brake) and the ECU.

Identify the earths for the ABS control unit and ABS motor their wire colours what pins numbers.

The earths and the colours are 10B and 7B whereas the colour is white /black and the pin numbers and colours for ABS motor is 1A and the colour of the wire is white / black.

On the wiring diagram for the ABS actuator, identify which solenoids control which wheel cylinder. Then note the wire colours and pin numbers.

Front Right Wheel : Pin number - 2B/6B and the Wire colour - Red White / Red Green

Front Left Wheel : Pin number - 3B/7B and the Wire colour - Blue Red / Blue White

Rear Left Wheel : Pin number - 1B/5B and the Wire colour - Brown White / Brown Red

Rear Right Wheel : Pin number - 4B/8B and the Wire colour - Green Black / Green Yellow

Using the picture above as a guide, which of the following gives the correct condition of the inlet and outlet solenoids valves under normal braking?

B - inlet valve open and outlet valve closed.

Using the picture above as a guide, which of the following gives the correct conditions of the inlet and outlet solenoids valves when the ABS is operating to reduce wheel brake pressure?

C - inlet valve closed and the outlet valve open

Using the picture above as a guide, which of the following gives the correct condition of the inlet and outlet solenoids valves when the ABS is operating to hold brake preesure?

D - inlet valve closed and the outlet valve closed.

Using the picture above as a guide, which of the following gives the correct condition of the inlet and outlet solenoids valves when the ABS is operating to increase wheel brake pressure?

B - inlet valve open and the outlet valve closed.

In the four cases above state when the ABS motor will be working?

Case two: It will be working only to reduce the wheel brake pressure.

There are three main types of wheel sensors on modern vechicles. One sends an analogue signal using and inductive pick up, the others send a digital signal using ether hall effect or magneto-resistant encoder.

On the graph below draw a digital signal switches 5volts every 2 seconds. Mark volt and time scales on the graph that will show the signal well.

On the graph below draw an analogue signal with a frequency of 0.5Hz and a maximum of +3 volts. Mark volt and time scales on graph that will show the signal well.