Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Vehicle speed sensor ”a” / Circuit description
Toyota Corolla (E120): Circuit description
The vehicle equipped with abs detects a vehicle speed using the stability control ecu and wheel speed sensor. This sensor monitors a wheel rotation speed and sends the signal to the ecu.
The stability control ecu converts these wheel speed signals into a 4–pulse signal and outputs it to the ecm via the combination meter.
The ecm determines the vehicle speed based on the frequency of these pulse signals.
In the vehicle without abs, the no. 1 Vehicle speed sensor outputs a 4–pulse signal for every revolution of the rotor shaft, which is rotated by the transmission output shaft via the driven gear. After this signal is converted into a more precise rectangular waveform by the waveform shaping circuit inside the combination meter, it is then transmitted to the ecm. The ecm determines the vehicle speed based on the frequency of these pulse signal.
W/ abs:
W/o abs:
Monitor description
Equipped with abs:
the ecm assumes that the vehicle is driven when the rpm of the transmission counter gear indicates more than 300 rpm and it has been over 30 seconds since the park/neutral position switch was turned off. If there is no signal from the vehicle speed sensor with these conditions satisfied, the ecm concludes that there is a fault in the vehicle speed sensor. The ecm will turn on the mil and a dtc is set.
Not equipped with abs:
the ecm assumes that the vehicle is driven when the park/neutral position switch is off and it has been over 4 seconds since the actual vehicle speed was 9 km/h or more.
If there is no signal from the vehicle speed sensor with these conditions satisfied, the ecm concludes that there is a fault in the vehicle speed sensor. The ecm will turn on the mil and a dtc is set.
Monitor strategy
Typical enabling conditions
Typical malfunction thresholds
Wiring diagram
Other materials:
Replacement
1. Remove radiator grille sub–assy
2. Remove front bumper cover
3. Remove fog lamp assy lh
Remove a nut and release a claw.
remove the fog light assy lh.
4. Put vehicle these conditions
5. Adjust fog light aim
6. Check fog light aim ...
Preparations to use wireless communication
The following can be performed using Bluetooth® wireless communication:
■ A portable audio player can be operated and listened to via multimedia system
■ Hands-free phone calls can be made via a cellular phone In order to use wireless
communication, register and connect a Bluetooth ...
On–vehicle inspection
1. Inspection throttle body idle speed control valve assy
Notice:
it is impossible to check the resister value and the operation
of isc valve by itself, because the isc valve
has an ic circuit inside it, which transforms the duty
signal from the ecm to the derive signal.
After check ...