Method 1: Using a Diagnostic Connector and a Test Light (Most Common)
1. Locate the Diagnostic Connector (DLC): This is usually a rectangular connector under the dashboard, often near the steering column. It might have a single connector or a pair. The exact location can vary slightly between years and trim levels, so consult your owner's manual or search online for a picture of the DLC location in a 1995 Chevy Blazer.
2. Jump the Connector: You'll need to jump two specific terminals within the DLC. This is usually done by inserting a wire or paper clip into two pins within the connector. The specific pins to jump vary depending on your year and exact model. You will need to find a wiring diagram for your specific vehicle to determine the correct pins. Online forums for Chevy Blazer owners are your best bet for this information. Search for "1995 Chevy Blazer OBD1 diagnostic connector pinout" or something similar. Do not attempt this without knowing the correct pins; jumping the wrong ones could damage your vehicle.
3. Connect a Test Light: Connect one lead of your test light to a good ground (like an unpainted metal part of the chassis), and the other lead to one of the connector pins (this will depend on your specific pinout).
4. Monitor the Test Light: Turn the ignition key to the "ON" position (don't start the engine). The test light will flash a code. Each flash represents a digit in the code. For example, a flash, pause, two flashes would be code 12. The pause between digits will usually be longer than the pause between flashes within a digit.
5. Record the Codes: Write down the codes as they flash. You'll need to look up the meaning of these codes in a 1995 Chevy Blazer OBD-I trouble code manual or online (again, using specific search terms for your year and model).
Method 2: Using a Specific OBD-I Scanner:
Some older OBD-I scanners are available that are specifically designed to work with this type of system. These scanners will usually plug directly into the DLC and display the codes on a screen, eliminating the need for the test light and interpreting the flashes.
Important Considerations:
* Safety: Always disconnect the negative battery terminal before working on your vehicle's electrical system.
* Accuracy: The test light method can be prone to error, so take your time and carefully record the codes.
* Information Sources: Online forums dedicated to 1995 Chevy Blazers are invaluable for finding specific information about the DLC pinout and trouble codes. Your owner's manual might also have some basic diagnostic information, but it likely won't be very detailed.
Finding the correct pinout for your specific vehicle is the most crucial step. Proceed with caution and double-check your information before jumping the connector. If you're unsure about any of these steps, it's best to take your vehicle to a qualified mechanic for diagnosis.
