Vehicle Speed Sensor
2021 Toyota RAV4 · 2.5L I4
Sensor Type
hall-effect
Waveform Type
dc-square
Location
Mounted on transaxle case, driver side near left axle output shaft, reading reluctor on differential carrier
Pins
3-pin connector
Timebase
20ms/div at 25mph, 10ms/div at 50mph
Voltage Scale
5V/div
Trigger
6V, rising edge
Wiring
Yellow wire (signal output to ECM pin 33), Red wire (power supply +12V), Black wire (ground)
Expected Voltage Range
At Idle
0V to 0V
At Higher RPM
0.2V to 12V
Expected Pattern
Digital square wave switching between 0V and 12V, 4 pulses per axle shaft revolution, clean transitions with rise time under 1 microsecond
Known-Good Waveform
At 25mph, expect crisp square wave alternating between approximately 0.3V (low) and 11.5-12.5V (high) with frequency around 12-15Hz. Duty cycle should be 50% ±5%. Edges should be vertical with no rounding or ringing, and voltage levels should be stable with less than 0.5V variation during transitions.
Common Failure Patterns
No signal, voltage stuck at 0V or 12V regardless of vehicle movement
Cause: Failed Hall-effect IC in sensor, no power supply to sensor, open signal wire
Intermittent signal dropouts, missing pulses at random
Cause: Corroded connector terminals, damaged wiring harness flexing near sensor, failing sensor IC
Signal present but irregular frequency or erratic pulse width
Cause: Damaged reluctor teeth, excessive endplay in differential allowing air gap variation, metallic debris on sensor face
Related DTCs: P0503
Slow rise/fall times, rounded edges instead of square wave
Cause: Excessive resistance in power or ground circuit, failing sensor output transistor
Related DTCs: P0503
Diagnostic Tips
ECM calculates vehicle speed from this sensor for speedometer, CVT control, and cruise control on FWD RAV4. Verify 12V power supply at sensor connector with ignition on. This sensor supplements ABS wheel speed data; ECM will detect mismatch between VSS and wheel speeds. Clean magnetic sensor tip and check for metal shavings indicating transaxle wear.
Related Diagnostic Trouble Codes
P0500P0501P0502P0503
Always confirm waveform data with your vehicle's OEM service manual before diagnosing.
Free, no signup. View all waveforms for this vehicle