CAN - Multiplexing Worksheet

1.0 CAN Waveform on Oscilloscope

1.1 Locate the Range Rover or other suitable vehicle with easily accessible CAN system twisted wires. Which vehicle do you have? ( Year, make, and model).

The Range Rover , Land Rover, 2001.

1.2 Locate a twisted wire pair. Describe where the wires are located:

It is located under the bonnet on the passengers side and connected to the hydraulic Control Unit.

1.3 Record the waveform of one of the wires below: (Make sure your time is small enough so you don't have "aliasing".)

Colour of the wire: Yellow with brown stripe

Time per division: 200ms

Voltage Per Division: 1V per division

1.4 Record the waveform of the other wire in the twisted pair.

Colour of wire: Yellow with black stripe.

Time per division: 200ms

Voltage per division: 1V per division

1.5 What is aliasing? Describe it.

It's a signal , processing , computer graphics and related displines aliasing refers to an effect that cause different continuous signals to be indistinguishable when sampled. When the digital image is viewed it is performed by a diplay or printer device therefore the reconstructed image will differ from the original image and an alias is seen.

1.6 How do you know these waveforms are not "aliasing"?

It is because they are clear to read and understand

1.7 In the 1.3 waveform above, what is the main voltage on the line?

2.5V

What is the other voltage on the line, when the voltage is pulled up or down to "talk"?

1.5V

1.8 In the 1.4 waveform above, what is the main voltage on the line?

2.5V

What is the voltage on the line, when the voltage is pulled up or down to "talk"?

3.5V

1.9 Observe the signals in 1.3 and 1.4 above with a voltmeter. Compare it with DC volts or AC volts setting. Which setting would tell you if the signal is swtching. Explain:

The comparison between the DCV and ACV the AC tells the signal of switching which is illustrating either "on" or "off"

Yellow/Brown DCV = 2.63 and ACV = 0.23

Yellow/Black DCV = 0.26-0.318 and ACV = 0.005

According to the observation we found out by using the volts meter it does not tells the good reading compared to the scan tool.