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:
Check short circuit
If the wire harness is ground shorted as shown in fig. 5,
Locate the section by conducting a resistance check with
the body ground in step (b).
Check the resistance with the body ground.
Disconnect connectors a and c and measure the
resistance between terminals 1 and 2 ...
Circuit description
The o/d main switch (transmission control switch) is a momentary type switch.
When pressing the o/d main
switch, the o/d off indicator light lights up and the ecm prohibits shifting
into o/d, and when pressing it
once again, the o/d off indicator light goes off and the ecm allows shifting
in ...
Inspection
1. Intake air flow meter sub–assy
Inspect the intake air flow meter resistance.
Using an ohmmeter, measure the resistance between
terminals tha and e2.
Resistance:
at –20 c (–4 f) 13.6 To 18.4 KΩ
at 20 c (68 f) 2.21 To 2.69 KΩ
at 60 c (140 f) 0.49 To 0.67 ...


