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P0502

DTC P0502 VEHICLE SPEED SENSOR CIRCUIT LOW INPUT

1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of vehicle speed sensor.
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 (USED WITH ABNORMAL JUDGEMENT)

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

4. DIAGNOSTIC METHOD




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




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

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

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

7. FAIL SAFE
- Vehicle speed sensor signal process: Vehicle speed = 10 km/h (6 MPH)
- ISC control: Set the open loop compensation to specified value (1 g (0.04 oz)/s). Not allowed ISC feedback volume calculation.
- Radiator fan control: ON both main/sub.
- Tumble generator valve control: Open the tumble generator valve.

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