Crankshaft Position Sensor
2021 Honda Accord · 1.5L I4 Turbo
Sensor Type
hall-effect
Waveform Type
dc-square
Location
Front lower right side of engine block, near crankshaft pulley, positioned at approximately 2 o'clock when viewing from front of engine
Pins
3-pin connector
Idle Frequency
25 Hz
Timebase
20ms/div
Voltage Scale
2V/div
Trigger
2.5V, rising edge
Wiring
Orange (signal), Black (ground), White/Blue (5V reference)
Expected Voltage Range
At Idle
0.2V to 4.8V
At Higher RPM
0.2V to 4.8V
Expected Pattern
58 teeth with 2 missing teeth creating sync gap, square wave pulses transitioning between 0V and 5V
Known-Good Waveform
Clean square wave transitioning sharply between near 0V (0.2V) and near 5V (4.8V) with consistent frequency at idle around 25Hz (1500 RPM). The missing tooth gap should show approximately 3x normal tooth spacing and occur once per crankshaft revolution. Rise and fall times should be less than 5 microseconds with no ringing or oscillation.
Common Failure Patterns
Intermittent dropout of signal or complete loss, waveform shows flat line at 0V or 5V
Cause: Internal Hall effect IC failure or broken wire in harness near sensor connector due to heat and vibration
Erratic voltage levels, signal doesn't reach full 5V or drops below 0.5V, slow rise/fall times
Cause: Corroded connector pins or water intrusion in connector, poor ground connection
Diagnostic Tips
Honda CKP sensors on this engine are sensitive to oil contamination on the reluctor ring - check for oil leaks from front main seal. Verify 5V reference voltage is stable; voltage drops under 4.8V indicate PCM power supply issues common on these models.
Related Diagnostic Trouble Codes
P0335P0336P0337P0338P0339
Always confirm waveform data with your vehicle's OEM service manual before diagnosing.
Free, no signup. View all waveforms for this vehicle