Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Cruise control system / Actuator magnetic clutch circuit / Circuit description
Toyota Corolla (E120): Circuit description
This circuit turns on the magnetic clutch inside the actuator during cruise control operation according to the signal from the ecu. If a malfunction occurs in the actuator or speed sensor, etc. During cruise control operation, the rotor shaft between the motor and control plate is released.
When the brake pedal is depressed, the stop lamp switch assy turns on, supplying electrical power to the stop light. Power supply to the magnetic clutch is mechanically cut and the magnetic clutch is turned off.
When driving downhill, if the vehicle speed exceeds the set speed by 8 km/h (5 mph), the ecu turns the safety magnet clutch off. If the vehicle speed later drops to within 5 km/h (3 mph) above the set speed, then cruise control at the set speed is resumed.

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 ...
Circuit description
While driving uphill with cruise control activated, in order to minimize gear
shifting and provide smooth cruising
overdrive may be prohibited temporarily under some conditions.
The cruise control ecu sends o/d cut signals to the ecm as necessary and the ecm
cancels overdrive
shifting until ...
Terminals of ecu
Oscilloscope wave (*1)
Hint:
terminal: od – gnd
gauge set: 5 v / div, 50 ms / div
condition: during cruise control driving o/d switch on.
...


