I have a chevy trailblazer 2002 4 whl drive and I get a code of b0222 front wheel speed signal missing. I understand there is a signal wire in there somewhere but I can't find it. Is there a schematic for this anywhere so I can find where it goes.
Answer: Each wheel has a speed sensor. The speed sensor has 2 wires that plug into it. The ABS computer looks at the AC voltage signal created by the wheel speed sensor on the 2 wires.
You can either remove the wheel or just crawl under the truck to located the wires. They are in a black plastic insulator. They run from the back side of the wheel bearing hub, to the lower control arm, to the frame and then to the computer. You either have a broken wire, or the wheel speed sensor is bacd.
To not guess at which is bad, you would need to unplug the wheel speed sensor, use a volt meter on AC voltage scale, spin the wheel and look for voltage on your meter. Or use the meter on the OHM scale to test the sensor. You should between 900 and 1300 OHMS. If either of these tests fail, the sensor is bad. If these test good, then you have a broken wire between the sensor and the computer.
