Advanced Diagnostics

Advanced Diagnostics - DTC P0502: CVT Speed Sensor Circuit Open/Short











General Description
The vehicle speed sensor is attached to the outside of the transmission housing. The vehicle speed sensor detects the number of revolutions of the secondary driven gear and sends a pulsing signal to the powertrain control module (PCM). The PCM converts the pulsing signal into vehicle speed. If no pulses occur with the secondary driven gear rotating, the PCM detects a malfunction that may be caused by an open, a temporary open, or a short to ground. Based on the correlation between the vehicle speed sensor and the CVT output shaft (driven pulley) speed sensor, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status






Enable Conditions






Malfunction Threshold
The driven pulley speed measured by the vehicle speed sensor is 100 rpm or less for at least 4 seconds when the vehicle speed measured by the CVT output shaft (driven pulley) speed sensor is 8 mph (14 km/h) or more.

Driving Pattern






1. Start the engine.
2. Drive the vehicle at a speed of 25 mph (40 km/h) or more.
3. Release the accelerator pedal, and slow down the vehicle for more than 6 seconds.

- Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.

Diagnosis Details

Conditions for setting the DTC
When a malfunction is detected, the MIL comes on and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the PCM memory.

Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.