Using Scan Tools to Read OBD-II Codes

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Objective

I can use a scan tool to connect to the DLC, retrieve specific DTCs, and determine the readiness status of OBD-II monitors.

Part 1 of 4

Warm-up video

1A Auto: Repair Tips & Secrets Only Mechanics Know · 3:03

We don't generate video — this one is by 1A Auto: Repair Tips & Secrets Only Mechanics Know on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.

Part 2 of 4

Key concepts

3 concepts

  1. 1

    When the battery is disconnected, all monitors are cleared, which can affect emission inspections.

  2. 2

    A scan tool can be used to check if the monitors are ready before going to a shop for a state inspection.

  3. 3

    The DLC connector is typically located underneath the driver's side and is used to connect the scan tool to the car's computer.

Part 3 of 4

Practice

11 questions

1

What is the primary function of OBD-II monitors?

2

Where is the DLC connector typically located in most cars?

Part 4 of 4

Exit ticket

Quick comprehension check

Using a scan tool, connect to the DLC of a car with the ignition on. After the scan tool has checked the monitors, what information is displayed regarding DTCs, the number of completed readiness monitors, and the number of non-completed readiness monitors?

Sample answer included in the free materials

Get the materials

Teacher guide, student handout, and slides — free, in Google Docs format

  • Teacher Guide

    Complete lesson plan with answer keys and alternate activities

  • Student Handout

    Printable worksheet

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