Did you measure the resistance from either sensor wire to ground?
I can get you started with a few comments of value. The first is these GM front-wheel-drive cars are notorious for many repeat failures due to the normal play that develops in the front wheel bearings. The dealer's scrap metal bins are full of these. (By the way, the old ones will work just fine on cars without ABS). Those sensors develop real wimpy signals to start with, then, when a little normal play develops in the bearings, the tone ring moves away from the sensor far enough to reduce the signal strength even more, to the point the computer can't read it. Movement between parts is always a requirement, so since the signal strength goes down as road speed decreases, this usually results in false activation at low speeds. It is real common for a new bearing assembly to cause the same problem after as little as 15,000 miles.
Next, you can't use a digital voltmeter to read these signals. The AC Volts range is only accurate with a 60 hertz sine wave. These sensors develop a square-wave signal at a much higher frequency. If you have a "Frequency" range on your meter, you are likely to get a reading, but that won't tell you if it's high enough in voltage to be read by the computer. The best we can do is use a scanner to view live data and see what the computer is seeing.
Since you are obviously not a do-it-yourselfer, there is one more thing I've heard multiple times in training classes. There was a software glitch with some scanners that only pertained to some '90s GM vehicles. It would confuse the front left and right sensors. I can't remember if it set a fault code for the wrong wheel, or if the square wave signals were switched on the graphing display. You might try performing the resistance tests on the other wheels. 1,000 ohms could be okay, but when I've measured these sensors, it's more common to find around 400 - 800 ohms. The point is you don't have an open circuit.
Sunday, March 31st, 2019 AT 12:19 AM