1Nz-Fe Engine Control. Dtc P0500 Vehicle Speed Sensor A

The vehicle speed is detected using the No. 1 vehicle speed sensor. The No. 1 vehicle speed sensor transmits a 4-pulse signal for every revolution of the rotor shaft, which is rotated by the transaxle output shaft via the driven gear. The 4-pulse signal is converted into a more precise rectangular waveform by the waveform shaping circuit inside the combination meter. The signal is then transmitted to the ECM. The ECM determines the vehicle speed based on the frequency of the pulse signal.

Yaris. Ncp93, 131.1Nz-Fe Engine Control.Sfi System (For Sedan).
Dtc
P0500 Vehicle Speed Sensor A

DTC No.	DTC Detection Condition	Trouble Area
P0500	While vehicle being driven, no vehicle speed sensor signal transmitted to ECM (1 trip detection logic: Automatic transaxle) (2 trip detection logic: Manual transaxle)	Open or short in speed signal circuit Vehicle speed sensor Combination meter ECM Wire harness or connector

MONITOR DESCRIPTION

Automatic Transaxle Models
The ECM assumes that the vehicle is being driven when the indicated engine speed is more than 2080 rpm and 30 seconds have elapsed since the Park/Neutral Position (PNP) switch was turned OFF (typical example values). If there is no speed signal from the combination meter, 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 Transaxle Models
The ECM assumes that the vehicle is being driven when fuel cut with the accelerator pedal released continues for 5 seconds or more. If there is no speed signal from the combination meter, despite this 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

Related DTCs	P0500: Vehicle speed sensor "A" pulse input error
Required Sensors/Components (Main)	Vehicle Speed Sensor (VSS), Combination meter and Skid control ECU
Required Sensors/Components (Related)	Park/Neutral Position (PNP) switch, Engine Coolant Temperature (ECT) sensor, Crankshaft Position (CKP) sensor, Throttle Position (TP) sensor and Mass Air Flow (MAF) meter
Frequency of Operation	Continuous
Duration	2 seconds: Automatic transaxle, Intake air temperature -10°C (14°F) or more 8 seconds: Automatic transaxle, Intake air temperature less than -10°C (14°F) 4.25 seconds: Manual transaxle
MIL Operation	Immediate: Automatic transaxle 2 driving cycles: Manual transaxle
Sequence of Operation	None

TYPICAL ENABLING CONDITIONS

M/T:
Monitor runs whenever following DTCs not present	None
Time after ignition switch turned from OFF to ON	3 seconds or more
Battery voltage	8 V or higher
Ignition switch	ON
Starter	OFF
Fuel-cut	ON

A/T:
Monitor runs whenever following DTCs not present	None
Ignition Switch	ON
Time after Ignition switch OFF to ON	3 seconds or more
Battery voltage	8 V or higher
Starter	OFF
Either of following conditions (a) or (b) met:	-
(a) Following conditions 1 and 2 met:	-
1. ECT and ECT sensor	20°C (68°F) or more, and sensor does not malfunction (P0115 or P00117, P0118, P0125)
2. Time after PNP switch turned OFF	10 seconds or more
(b) Following conditions 1 and 2 met:	-
1. ECT and ECT sensor	Less than 20°C (68°F), and sensor malfunction (P0115 or P0117, P0118, P0125)
2. Time after PNP switch turned OFF	30 seconds or more
TP sensor fail (P0120, P0121, P0122, P0123, P0220, P0222, P0223, P2135)	Not detected
Engine speed	2080 rpm or more (varies with throttle valve opening angle)
Fuel cut at high engine speed	Not executing
Time after Ignition switch OFF to ON	More than 0.5 seconds
TP sensor learning	Completed

TYPICAL MALFUNCTION THRESHOLDS

Vehicle speed sensor signal

No pulse input

CONFIRMATION DRIVING PATTERN

Connect the Techstream to the DLC3.
Turn the ignition switch to ON and turn the Techstream on.
Clear DTCs (even if no DTCs are stored, perform the clear DTC operation).
Turn the ignition switch off and wait for at least 30 seconds.
Turn the ignition switch to ON and turn the Techstream on [A].
Start the engine and warm it up until the ECT reaches 75°C (167°F) or higher [B].
Accelerate the vehicle to 74 km/h (46 mph) or higher [C].
Maintain the vehicle speed at 74 km/h (46 mph) or higher for 10 seconds or more [D].
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
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [F].
Read pending DTCs.
HINT:
1. If a pending DTC is output, the system is malfunctioning.
2. If a pending DTC is not output, perform the following procedure.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input the DTC: P0500.

Check the DTC judgment result.

Techstream Display	Description
NORMAL	DTC judgment completed System normal
ABNORMAL	DTC judgment completed System abnormal
INCOMPLETE	DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions
N/A	Unable to perform DTC judgment Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

HINT:

If the judgment result shows NORMAL, the system is normal.
If the judgment result shows ABNORMAL, the system has a malfunction.

If the result is INCOMPLETE or N/A and no pending DTC is output, perform a universal trip and check for permanent DTCs (YARIS_NCP93 RM000000PDK0QGX.html).
HINT:
1. If a permanent DTC is output, the system is malfunctioning.
2. If no permanent DTC is output, the system is normal.

WIRING DIAGRAM

INSPECTION PROCEDURE

HINT:

Various systems use the vehicle speed signal distributed from the combination meter. Check all the components possibly related to speed signal.
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.

1.CHECK OPERATION OF SPEEDOMETER

Drive the vehicle and check whether the operation of the speedometer in the combination meter is normal.
OK:
The operation of the speedometer is normal.
HINT:
1. The vehicle speed sensor is operating normally if the speedometer reading is normal.
2. If the speedometer does not operate, check it by following the procedure described in Speedometer Malfunction (YARIS_NCP93 RM000001DAL00MX.html).

GO TO MALFUNCTION IN SPEEDOMETER

OK

2.READ VALUE USING TECHSTREAM (VEHICLE SPEED)

Connect the Techstream to the DLC3.

Turn the ignition switch to ON.

Turn the Techstream on.

Enter the following menus: Powertrain / Engine and ECT / Data List / Vehicle Speed.

Drive the vehicle.

Read the value displayed on the Techstream.
OK:
Vehicle speeds displayed on the Techstream and speedometer display are equal.

Go to step 3

CHECK FOR INTERMITTENT PROBLEMS (YARIS_NCP93 RM000000PDQ0NOX.html)

3.CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM)

Disconnect the combination meter connector.

Disconnect the ECM connector.

Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open):
Tester Connection
Condition
Specified Condition
D1-16 - A21-8 (SPD)
Always
Below 1 Ω
Standard Resistance (Check for Short):
Tester Connection
Condition
Specified Condition
D1-16 or A21-8 (SPD) - Body ground
Always
10 kΩ or higher
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.).

Reconnect the combination meter connector.

Reconnect the ECM connector.

REPAIR OR REPLACE HARNESS OR CONNECTOR (OTHER SYSTEMS RELATED TO SPEED SIGNAL)

OK

4.CHECK COMBINATION METER (VOLTAGE)

Disconnect the combination meter connector.
HINT:
Disconnect the ECU connectors on the other systems related to the speed signal (but the ECM connectors must be connected).

Turn the ignition switch to ON.

Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection
Switch Condition
Specified Condition
D1-16 - Body ground
Ignition switch ON
4.5 to 5.5 V
Text in Illustration
*a
Front view of wire harness connector
(to Combination Meter)

Text in Illustration
*a	Front view of wire harness connector (to Combination Meter)

Reconnect the combination meter connector.

REPLACE ECM (YARIS_NCP93 RM000001CN002AX.html)

OK

5.INSPECT COMBINATION METER (SPD SIGNAL OUTPUT WAVEFORM)

Remove the combination meter assembly (YARIS_NCP93 RM000000IN001JX.html).

Connect the combination meter connector.

Move the shift lever to the neutral position.

Jack up the vehicle.

Turn the ignition switch to ON.

Check the voltage between the terminal of the combination meter and the body ground while the wheel is turned slowly.
Standard Voltage:
Tester Connection
Switch Condition
Specified Condition
D1-16 - Body ground
Ignition switch ON
(Turn wheel slowly)
Voltage generated intermittently
Text in Illustration
*a
Component with wire harness connected
(Combination Meter)
*b
Turn Wheel
HINT:
The output voltage should fluctuate up and down, similarly to the diagram, when the wheel is turned slowly.

Text in Illustration
*a	Component with wire harness connected (Combination Meter)
*b	Turn Wheel

Reinstall the combination meter assembly (YARIS_NCP93 RM000000IMY01KX.html).

Go to step 6

REPLACE ECM (YARIS_NCP93 RM000001CN002AX.html)

6.INSPECT COMBINATION METER (SPD SIGNAL INPUT WAVEFORM)

Remove the combination meter assembly (YARIS_NCP93 RM000000IN001JX.html).

Connect the combination meter connector.

Move the shift lever to the neutral position.

Jack up the vehicle.

Turn the ignition switch to ON.

Check the voltage between the terminal of the combination meter and the body ground while the wheel is turned slowly.
Standard Voltage:
Tester Connection
Switch Condition
Specified Condition
D1-17 - Body ground
Ignition switch ON
(Turn wheel slowly)
Voltage generated intermittently
Text in Illustration
*a
Component with wire harness connected
(Combination Meter)
*b
Turn Wheel
HINT:
The output voltage should fluctuate up and down, similarly to the diagram, when the wheel is turned slowly.

Text in Illustration
*a	Component with wire harness connected (Combination Meter)
*b	Turn Wheel

Reinstall the combination meter assembly (YARIS_NCP93 RM000000IMY01KX.html).

Result
Result	Proceed to
OK	A
NG	B

Go to step 7

REPLACE COMBINATION METER (YARIS_NCP93 RM000000IN001JX.html)

7.CHECK HARNESS AND CONNECTOR (COMBINATION METER - VEHICLE SPEED SENSOR)

Disconnect the combination meter connector.

Disconnect the vehicle speed sensor connector.

Measure the resistance according to the value(s) in the table below.
Standard Resistance (Check for Open):
Tester Connection
Condition
Specified Condition
D1-17 - C21-3 (SI)
Always
Below 1 Ω
Standard Resistance (Check for Short):
Tester Connection
Condition
Specified Condition
D1-17 or C21-3 (SI) - Body ground
Always
10 kΩ or higher

Reconnect the combination meter connector.

Reconnect the vehicle speed sensor connector.

REPAIR OR REPLACE HARNESS OR CONNECTOR

REPLACE VEHICLE SPEED SENSOR

Tester Connection	Condition	Specified Condition
D1-16 - A21-8 (SPD)	Always	Below 1 Ω

Tester Connection	Switch Condition	Specified Condition
D1-16 - Body ground	Ignition switch ON	4.5 to 5.5 V