Engine Control System - SFI System

2GR-FE ENGINE CONTROL: SFI SYSTEM: P0500: Vehicle Speed Sensor "A"

DTC P0500 - Vehicle Speed Sensor "A"

DESCRIPTION

The wheel speed sensors monitor the wheel rotation speed and send signals 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 assembly. The ECM determines the vehicle speed based on the frequency of the pulse signal.
HINT:
- A voltage of 12 V or 5 V is output from each ECU and then input to the combination meter assembly. The signal is changed to a pulse signal at the transistor in the combination meter assembly. Each ECU controls the respective system based on the pulse signal.
- If a short occurs in any of the ECUs or in the wire harness connected to an ECU, all systems in the wiring diagram below will not operate normally.









*1: w/ Smart Key System
*2: for Separate Type Amplifier System
*3: w/ Navigation System
*4: w/ Automatic Type Headlight Beam Level Control

MONITOR DESCRIPTION

If there is no speed signal from the combination meter even though the ECM determines that the vehicle is being driven, 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





CONFIRMATION DRIVING PATTERN





1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON and turn the Techstream on [A].
3. Clear the DTCs (even if no DTCs are stored, perform the Clear DTC procedure) DTC Check / Clear.
4. Start the engine.
5. Drive the vehicle at 15 mph (24 km/h) or more for a total of 30 seconds or more [B].
6. Stop the vehicle.
7. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
8. Input the DTC: P0500.
9. Check the DTC judgment result [C].





HINT: If the judgment result shows ABNORMAL, the system has a malfunction.

10. If the test result is UNKNOWN, enter the following menus: Powertrain / Engine / Trouble Codes / Pending.
11. Read Pending DTCs.
HINT: If a pending DTC is output, the system is malfunctioning.

12. If the test result is INCOMPLETE or UNKNOWN and no pending DTC is output, perform a universal trip and check for permanent DTCs DTC Check / Clear.
HINT:
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.

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. READ VALUE USING TECHSTREAM (VEHICLE SPEED)
(a) Drive the vehicle and check whether the operation of the speedometer in the combination meter assembly is normal.
HINT:
- The vehicle speed sensor is operating normally if the speedometer reading is normal.
- If the speedometer does not operate, check it by following the procedure described for a speedometer malfunction.
(b) Connect the Techstream to the DLC3.
(c) Turn the ignition switch to ON.
(d) Turn the Techstream on.
(e) Enter the following menus: Powertrain / Engine / Data List / Vehicle Speed.
(f) Drive the vehicle.
(g) Read the value displayed on the Techstream.
OK:
Vehicle speeds displayed on the Techstream and speedometer display are equal.

NG -- CHECK COMBINATION METER ASSEMBLY (SPD SIGNAL WAVEFORM)
OK -- CHECK FOR INTERMITTENT PROBLEMS
2. CHECK COMBINATION METER ASSEMBLY (SPD SIGNAL WAVEFORM)




(a) Inspect the combination meter assembly using an oscilloscope.
(1) Move the shift lever to N.
(2) Jack up the vehicle.
(3) Turn the ignition switch to ON.
(4) Measure the voltage between the terminal of the combination meter assembly and the body ground while the wheel is turned slowly.
Standard Voltage:





Text in Illustration





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

NG -- GO TO METER / GAUGE SYSTEM (SPEED SIGNAL CIRCUIT)
OK -- Continue to next step.

3. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - ECM)
(a) Disconnect the combination meter assembly connector.




(b) Disconnect the ECM connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance :





Text in Illustration





(d) Reconnect the combination meter assembly connector.
(e) Reconnect the ECM connector.

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (COMBINATION METER ASSEMBLY - ECM)
OK -- REPLACE ECM