One sensor at each wheel hub - front sensors mounted in steering knuckle, rear sensors mounted in axle tube ends near differential
Pins
2-pin connector
0
Timebase
10ms/div at 15 mph, 5ms/div at 30+ mph
Voltage Scale
2V/div
Trigger
2.5V, rising edge
Wiring
Front Left: Dark Blue/Orange (signal) and Black/Light Blue (ground); Front Right: Light Blue/Brown (signal) and Black/Light Blue (ground); Rear sensors: Dark Green/Orange and Light Green/Orange (signals) with Black/Light Blue grounds
Expected Voltage Range
At Idle
0V to 5V
At Higher RPM
0V to 5V
Expected Pattern
Digital square wave switching between 0V and 5V (or 0V and battery voltage depending on year). 45-47 pulses per wheel revolution from tone ring teeth
Known-Good Waveform
Clean square wave alternating between 0V and approximately 5V with crisp transitions. Frequency increases proportionally with wheel speed - at 15 mph expect approximately 18-20 Hz. All four sensors should show matching frequencies when driving straight, with slight variations in turns as expected from differential action.
Common Failure Patterns
No signal or flat line at 0V
Cause: Failed sensor, broken wire, corroded connector, or damaged tone ring with missing teeth
JK Wranglers with aftermarket lift kits or larger tires commonly trigger WSS codes due to differential wheel speeds confusing ABS logic. Always compare all four sensor signals simultaneously to identify outliers. Front sensors are exposed to more debris and impact damage from off-road use.
Related Diagnostic Trouble Codes
C0035C0040C0045C0050
Always confirm waveform data with your vehicle's OEM service manual before diagnosing.