SFI System
1GR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0500: Vehicle Speed Sensor "A"
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 (brake actuator assembly) and wheel speed sensor. The wheel speed sensor monitors the wheel rotation speed and sends a signal to the skid control ECU (brake actuator assembly). The skid control ECU (brake actuator assembly) 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
* Various systems use the vehicle speed signal distributed from the combination meter. Check all the components possibly related to speed signal.
* 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 using the speed signal will not operate normally.
MONITOR DESCRIPTION
Automatic Transmission Models:
The ECM assumes that the vehicle is being driven when the indicated vehicle speed is 9 km/h (5.59 mph) or more. If these is no speed signal from the combination meter assembly despite these conditions being met, the ECM interprets this as a malfunction in the speed signal circuit. The ECM then illuminates the MIL and stores the DTC.
Manual Transmission Models:
The ECM assumes that the vehicle is being driven when the idle fuel-cut operation is being executed. If these is no speed signal from the combination meter assembly, despite these condition being met, the ECM interprets this as a malfunction in the speed signal circuit. The ECM then illuminates the MIL and stores the DTC.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
All
Manual Transmission
Automatic Transmission
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.
3. Clear DTCs (even if no DTCs are stored, perform the clear DTC operation).
4. Turn the ignition switch off and wait for at least 30 seconds.
5. Turn the ignition switch to ON and turn the Techstream on [A].
6. Start the engine and warm it up until the ECT reaches 75°C (167°F) or higher [B].
7. Accelerate the vehicle to 75 km/h (47 mph) or higher with the accelerator pedal opening angle of 20% or more [C].
CAUTION:
When performing the confirmation driving pattern, obey all speed limits and traffic laws.
8. Maintain the vehicle speed at 75 km/h (47 mph) or higher for 10 seconds or more [D].
CAUTION:
When performing the confirmation driving pattern, obey all speed limits and traffic laws.
9. Decelerate the vehicle by releasing the accelerator pedal for 5 seconds or more to perform fuel cut [E].
CAUTION:
When performing the confirmation driving pattern, obey all speed limits and traffic laws.
10. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [F].
11. Read pending DTCs.
HINT
* If a pending DTC is output, the system is malfunctioning.
* If a pending DTC is not output, perform the following procedure.
12. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
13. Input the DTC: P0500.
14. Check the DTC judgment result.
HINT
* If the judgment result shows NORMAL, the system is normal.
* If the judgment result shows ABNORMAL, the system has a malfunction.
15. If the judgment result is INCOMPLETE or N/A and no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.
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 help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.
PROCEDURE
1. CHECK OPERATION OF SPEEDOMETER
(a) Drive the vehicle and check whether the operation of the speedometer in the combination meter assembly is normal.
OK:
The operation of the speedometer 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 in Speedometer Malfunction Speedometer Malfunction.
NG -- GO TO MALFUNCTION IN SPEEDOMETER Speedometer Malfunction
OK -- Continue to next step.
2. READ VALUE USING TECHSTREAM (VEHICLE SPEED)
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Data List / Vehicle Speed.
(e) Drive the vehicle.
(f) Read the value displayed on the Techstream.
OK:
Vehicle speeds displayed on the Techstream and speedometer display are equal.
NG -- CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - ECM)
OK -- CHECK FOR INTERMITTENT PROBLEMS Check for Intermittent Problems
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:
HINT
If the wire has a short, check the speed signal circuit in other systems related to the vehicle speed signal (e.g. tire pressure warning system, audio system, etc.).
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (OTHER SYSTEMS RELATED TO SPEED SIGNAL)
OK -- Continue to next step.
4. CHECK COMBINATION METER ASSEMBLY (VOLTAGE)
(a) Disconnect the combination meter assembly connector.
HINT
Disconnect the ECU connectors on the other systems related to the speed signal (but the ECM connectors must be connected).
(b) Turn the ignition switch to ON.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Text in Illustration
NG -- REPLACE ECM Removal
OK -- Continue to next step.
5. CHECK COMBINATION METER (SPD SIGNAL OUTPUT WAVEFORM)
(a) Remove the combination meter assembly Removal.
(b) Connect the combination meter assembly connector.
(c) Move the shift lever to the N (Neutral).
(d) Jack up the vehicle.
(e) Turn the ignition switch to ON.
(f) Check 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 -- CHECK COMBINATION METER (SPD SIGNAL INPUT WAVEFORM)
OK -- REPLACE ECM Removal
6. CHECK COMBINATION METER (SPD SIGNAL INPUT WAVEFORM)
(a) Remove the combination meter assembly Removal.
(b) Connect the combination meter connector.
(c) Move the shift lever to the neutral position.
(d) Jack up the vehicle.
(e) Turn the ignition switch to ON.
(f) Check 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.
Result
B -- CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - BRAKE ACTUATOR ASSEMBLY)
A -- REPLACE COMBINATION METER ASSEMBLY Removal
7. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - BRAKE ACTUATOR ASSEMBLY)
(a) Disconnect the combination meter assembly connector.
(b) Disconnect the brake actuator assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Result
B -- REPLACE BRAKE ACTUATOR ASSEMBLY Removal
A -- REPAIR OR REPLACE HARNESS OR CONNECTOR