LED test lights didn't exist in the early '90s. There were some early Engine Computers that flashed diagnostic fault codes but weren't capable of driving an incandescent light bulb. Those specified the codes had to be read with a separate LED or with an analog voltmeter. Those are the old style with a pointer. Swings of the pointer were easy to see. You could do it with a digital voltmeter too since the flashes occurred slow enough for the meter to keep up. You just had to be sure to watch it closely to get the right results.
Here's a link to an article that spells out retrieving the fault codes on your car:
https://www.2carpros.com/articles/diagnostic-trouble-codes-for-1995-and-earlier-mazda-cars-obd1
With the method described, you don't need a test light. You watch the Check Engine light, same as on many other car brands at that time.
Apr 25, 2021 at 3:32 PM
