P0503

DTC P0503 - VEHICLE SPEED SENSOR INTERMITTENT/ERRATIC/HIGH

OUTLINE OF DIAGNOSIS
Detect the open or short circuit of vehicle speed sensor.
Judge NG when high vehicle speed (240 km/h (149.1 MPH) or more) remains whereas it seemed to be in a usual driving speed.




ENABLE CONDITION

GENERAL DRIVING CYCLE
Perform the diagnosis continuously during fuel cut in deceleration.

DIAGNOSTIC METHOD




- Abnormality Judgment
Judge NG when the cumulative time of completing the malfunction criteria becomes more than 4 seconds.




- Normality Judgment
Judge OK and clear NG when the malfunction criteria are completed.

DTC CLEAR CONDITION
- When the OK idling cycle was completed 40 times in a row
- When " Clear Memory " was performed

MALFUNCTION INDICATOR LIGHT CLEAR CONDITION
- When the OK driving cycle was completed 3 times in a row
- When " Clear Memory " was performed

FAIL SAFE
- Throttle position sensor signal process: Fix the all closed position learning value at 0 °.
- Vehicle speed sensor signal process: Vehicle speed = 10 km/h (6 MPH)
- Fuel cut control: Vehicle speed = 0 km/h (0 MPH) / Not allowed to carry out the fuel cut.
- ISC open loop compensation: Fix the open loop compensation at 5%
- ISC feedback control: Not allowed to calculate the amount of ISC feedback.
- Air conditioner control: Air conditioner cut signal is not allowed driving acceleration.
- Radiator fan control: Both main and sub fan are in High driving.

ECM OPERATION AT DTC SETTING
Memorize the freeze frame data. (For test mode $02)