H4SO (2.5L SOHC)
DTC P0502 VEHICLE SPEED SENSOR "A" CIRCUIT LOW INPUT1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of vehicle speed. Judge NG when low vehicle speed (0 km/h (0 MPH)) remains whereas it seemed to be in a usual driving speed.
2. ENABLE CONDITION (FOR ABNORMALITY JUDGMENT ONLY)
Enable Condition:
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously during deceleration fuel cut.
4. DIAGNOSTIC METHOD
Abnormality Judgment
Judge as NG when the continuous time of meeting the malfunction criteria below becomes 4 seconds or more.
Time Needed for Diagnosis: 4 seconds
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
Normality Judgment
Judge as OK and clear the NG when all of the following criteria are established.
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 CONDITION
- 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 specified value (1 g (0.04 oz)/s). Not allowed to calculate ISC feed back amount.
- 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)