Unit standard 21090

Unit standard 21090

Demonstrate knowledge of automotive multiplex and databus applications, and diagnose faults

Version 1; Level 5; 6 credits

This is an elective unit standard for the Automotive Electrical and Mechanical strand of the National Certificate in Motor Industry (Advanced Technical) (Level 5).

Download full details of unit standard 21090.

What is this unit standard about?

People credited with this unit standard are able to:

  • identify and distinguish automotive multiplex and databus applications
  • diagnose faults in multiplex wiring systems.

Should I have completed any other unit standards first?

No.

How will this unit standard be assessed?

You will be required to:

  • prove your theory knowledge of automotive multiplex and databus applications, identifying differences, features, and manufacturing approaches
  • diagnose faults in multiplex wiring systems, including interpreting fault codes, isolating faults, and determining the cause of faults.

This will involve completing the following types of assessment:

  • case study
  • workplace report.

Special tools and equipment or range of work required

You will need:

  • a scan tool and multi-meter
  • access to vehicles with multiplex system faults.

Supporting resources

Supporting resources for this unit standard can be found on your ATech® Resources CD. The following links may also be useful:

1. Fault and diagnostic information on most of the major car brands. Use keywords like common faults
2. Circuit drawings with descriptions. Use keywords like drawing
3. Search engine, use keywords like CAN, network, software, and multiplex
4. Bosch CAN/Multiplex systems
5. CAN/Mutliplex systems on today's vehicles. Use keywords like auto stuff
6. Diagnostic Fault Codes for most car brands. Use keywords like trouble codes
7. ECU's.