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H4SO (2.5L SOHC)

DTC P0503 VEHICLE SPEED SENSOR "A" INTERMITTENT/ERRATIC/HIGH

1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of vehicle speed. Judge as NG when high vehicle speed (240 km/h (149 MPH) or more) is still present under the driving condition of the vehicle running at a certain 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)