H4SO U5
DTC P0502 VEHICLE SPEED SENSOR "A" CIRCUIT LOW INPUT1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of vehicle speed sensor. Judge as NG when low vehicle speed (0 km/h (0 MPH) or more) is still present under the driving condition of the vehicle running at a certain speed.
2. ENABLE CONDITION
Enable Conditions:
3. GENERAL DRIVING CYCLE
Perform diagnosis continuously during deceleration fuel cut at an engine speed of less than 4000 rpm.
4. DIAGNOSTIC METHOD
- Abnormality Judgment
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Time Needed for Diagnosis: 4000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
- Normality Judgment
Judge as OK and clear the NG if the continuous time while the following conditions are established is more than the predetermined time.
Time Needed for Diagnosis: Less than 1 second
5. DTC CLEAR CONDITION
- When the OK idling cycle is completed 40 times in a row
- When "Clear Memory" is performed
6. MALFUNCTION INDICATOR LIGHT CLEAR CONDITIONS
- When the OK driving cycle is completed 3 times in a row
- When "Clear Memory" is performed
7. FAIL SAFE
- Vehicle speed sensor signal process: Vehicle speed = 10 km/h (6 MPH)
- ISC control: Open loop compensation is set to (1 g (0.04 oz)/s). Not allowed ISC feedback volume calculation.
- Radiator fan control: Both main and sub fan ON
- Tumble generator valve control: Open the tumble generator valve.
8. ECM OPERATION AT DTC SETTING
Memorize the freeze frame data. (For test mode $02)