Code No. P0500: Vehicle Speed Sensor System <Vehicles without ABS/ASTC>

OPERATION

Power is supplied to the vehicle speed sensor from the engine control relay and is earthed to the body from the vehicle speed sensor.
A power voltage of 5 V is applied to the vehicle speed sensor from the engine-ECU (terminal code V/S).

FUNCTION

The vehicle speed sensor converts the vehicle speed to the voltage, and then input it into the engine-ECU.

TROUBLE JUDGEMENT

Check Conditions

More than 2 seconds have passed since the engine starting sequence was completed.
Engine speed is more than 2,200 r/min and is less than 4,000 r/min.
Manifold absolute pressure is more than 40 kPa and is less than 65 kPa.

Judgement Criterion

Vehicle speed sensor output voltage has not changed (no pulse signal is input) for 2 seconds.

FAIL-SAFE AND BACKUP FUNCTION

None

PROBABLE CAUSE

Failed vehicle speed sensor
Open/short circuit or harness damage in vehicle speed sensor circuit or loose connector contact
Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list

Refer to Data List Reference Table .

Item 4: Vehicle speed sensor

Q. Is the check result normal?

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

	Go to Step 2.

STEP 2. Perform voltage measurement at vehicle speed sensor connector.

Disconnect connector, and measure at harness side.
Ignition switch: ON
Voltage between terminal power supply line and body earth.

OK: System voltage

Q. Is the check result normal?

	Go to Step 3.

	Repair or replace the connector(s), or check and repair the harness of open circuit, and short circuit in power supply line between vehicle speed sensor connector and engine control relay connector.

STEP 3. Perform voltage measurement at vehicle speed sensor connector.

Disconnect connector, and measure at harness side.
Ignition switch: ON
Voltage between terminal V/S line and body earth.

OK: 4.9 - 5.1 V

Q. Is the check result normal?

	Go to Step 6.

	Go to Step 4.

STEP 4. Check of open circuit, and short circuit in V/S line between vehicle speed sensor connector and engine-ECU connector.

Q. Is the check result normal?

	Go to Step 5.

	Repair the connector(s) or wiring harness.

STEP 5. M.U.T.-III data list

Refer to Data List Reference Table .

Item 4: Vehicle speed sensor

Q. Is the check result normal?

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

	Replace the engine-ECU.

STEP 6. Perform resistance measurement at vehicle speed sensor connector.

Disconnect connector, and measure at harness side.
Resistance between terminal earth line and body earth.

OK: Continuity (2 Ω or less)

Q. Is the check result normal?

	Go to Step 7.

	Repair or replace the connector(s), or check and repair the harness of open circuit, and damage in earth line between vehicle speed sensor connector and body earth.

STEP 7. Check of damage in power supply line between vehicle speed sensor connector and engine control relay connector.

Q. Is the check result normal?

	Go to Step 8.

	Repair the connector(s) or wiring harness.

STEP 8. Check of damage in V/S line between vehicle speed sensor connector and engine-ECU connector.

Q. Is the check result normal?

	Go to Step 9.

	Repair the connector(s) or wiring harness.

STEP 9. Replace the vehicle speed sensor

After replacing the vehicle speed sensor, reconfirm whether the diagnosis code is set.

Q. Is the diagnosis code set?

	Replace the engine-ECU.

	Check end.