Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / ABS with EBD system / Right/Left front speed sensor circuit / Circuit description
Toyota Corolla (E120): Circuit description

The speed sensor detects wheel speed and transmits the appropriate signals to the ecu. These signals are used for control of the abs control system. Each of the front and rear rotors has 48 serrations.
When the rotors rotate, the magnetic field generated by the permanent magnet in the speed sensor induces an ac voltage.
Since the frequency of this ac voltage changes in direct proportion to the speed of the rotor, the frequency is used by the ecu to detect the speed of each wheel.

Hint
: Dtc no. C0200/31 and c1235/35 is the right front speed sensor.
Dtc no. C0205/32 and c1236/36 is the left front speed sensor.
Wiring diagram

Other materials:
On–vehicle inspection
1. Inspect refrigerant pressure with manifold gauge set
this is a method in witch the trouble is located by using
a manifold gauge set. Read the manifold gauge pressure
when the these conditions are established.
Test conditions:
temperature at the air inlet with the switch set
...
Monitor description
The battery supplies electricity to the ecm even when the ignition switch is
off. This electricity allows the
ecm store data such as dtc history, freeze frame data, fuel trim values, and
other data. If the battery voltage
falls below a minimum level, the ecm will conclude that there is a fault ...
On–vehicle inspection
1. Check battery electrolyte level
Check the electrolyte quantity of each cell (maintenance–free battery).
If under the lower level, replace the battery (or add distilled
water if possible) and check the charging
system.
check the electrolyte quantity of each cell ...


