Engine Control System: SFI System

1GR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0500: Vehicle Speed Sensor "A"

DTC P0500 - Vehicle Speed Sensor "A"

DESCRIPTION

Vehicles, which are equipped with ABS (Anti-lock Brake System), detect the vehicle speed using the skid control ECU and wheel speed sensor. The wheel speed sensor monitors the wheel rotation speed and sends a signal to the skid control ECU. The skid control ECU converts the wheel speed signal into a 4-pulse signal and transmits it to the ECM via the combination meter. The ECM determines the vehicle speed based on the frequency of the pulse signal.









MONITOR DESCRIPTION

The ECM assumes that the vehicle is being driven, the vehicle speed sensor signal is being transmitted by the combination meter. If there is no signal from combination meter, despite the ECM detects the speed signal from speed sensor No. 2, the ECM interprets this as a malfunction in the speed signal circuit. The ECM then illuminates the MIL and sets the DTC.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





WIRING DIAGRAM





INSPECTION PROCEDURE

HINT: Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air/fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

PROCEDURE

1. CHECK OPERATION OF SPEEDOMETER
(a) Drive the vehicle and check if the operation of the speedometer in the combination meter is normal.
OK:
Actual vehicle speed and the speed indicated on the speedometer are the same.

HINT: The vehicle speed sensor is operating normally if the speedometer reading is normal.

NG -- CHECK SPEEDOMETER CIRCUIT
OK -- Continue to next step.

2. INSPECT ECM (SPD VOLTAGE)




(a) Shift the shift lever to the neutral position.
(b) Jack up the vehicle.
(c) Turn the ignition switch on.
(d) Check the voltage between the terminals of the E6 and E7 ECM connectors as the wheel is turned slowly.
OK:





HINT: The output voltage should fluctuate up and down similarly to the diagram on the left when the wheel is turned slowly.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE ECM