Toyota 2007 CAMRY Manual page 251

ABS, TRAC and VSC (TMC Made)
System Outline
1. ABS Operation
If the brake pedal is depressed suddenly, the ABS controls the hydraulic pressure of the wheel cylinders for all the four
wheels to automatically avoid wheel locking and ensure the directional and steering stability of the vehicle. If the brake pedal
is depressed suddenly, the skid control ECU controls the solenoids in the actuators using the signals from the sensors to
move the brake fluid to the reservoir in order to release the braking pressure applied to the wheel cylinder. If the skid control
ECU detects that the fluid pressure in the wheel cylinder is insufficient, the ECU controls the solenoids in the actuators to
increase the braking pressure.
2. Traction Control Operation
The traction control system controls the engine torque, the hydraulic pressure of the driving wheel cylinders, slipping of the
wheels which may occur at start or acceleration of the vehicle, to ensure an optimal driving power and vehicle stability
corresponding to the road conditions.
3. VSC Operation
Unexpected road conditions, vehicle speed, emergency situation, and any other external factors may cause large under– or
over–steering of the vehicle. If this occurs, the VSC system automatically controls the engine power and wheel brakes to
reduce the under– or over–steering.
To reduce large over–steering :
If the VSC system determines that the over–steering is large, it activates the brakes for the outer turning wheels depending
on the degree of the over–steering to produce the moment toward the outside of the vehicle and reduce the over–steering.
To reduce large under–steering :
If the VSC system determines that the under–steering is large, it controls the engine power and activates the rear wheel
brakes to reduce the under–steering.
4. Fail Safe Function
If an error occurs in the skid control ECU, sensor signals, and/or actuators, the skid control ECU inhibits the brake actuator
control and inputs the error signal to the engine control module. According to the error signal, the brake actuator turns off the
solenoid and the engine control module rejects any electronically controlled throttle open request from the VSC system. As a
result, the vehicle functions regardless of the ABS, TRAC, and VSC systems.
: Parts Location
Code See Page
48 (2GR–FE)
A14 A14
52 (2AZ–FE)
A18 59
A19 59
A24 A 52 (2AZ–FE)
48 (2GR–FE)
A26 A26
52 (2AZ–FE)
48 (2GR–FE)
A35 A35
52 (2AZ–FE)
A40 A 59
A41 A 59
A42 B 59
A55 A 49 (2GR–FE)
A58 A 59
C1 A 50 (2GR–FE)
: Relay Blocks
Code See Page
1 22
250
Code
C1 B
C5 C5
C20
C24 B
C50
C55 B
C57
E8 C
E10
E13
E17
E31
E33
E34
Relay Blocks (Relay Block Location)
Engine Room R/B (Engine Compartment Left)
CAMRY (EM0250U)
See Page
54 (2AZ–FE)
50 (2GR–FE)
54 (2AZ–FE)
55 (2AZ–FE)
55 (2AZ–FE)
51 (2GR–FE)
51 (2GR–FE)
51 (2GR–FE)
56
56
56
56
56
56
57
Code See Page
E40 B 57
E41 B 57
E42 A 57
E43 B 57
E44 C 57
E46 E 57
E49 57
E62 G 57
E63 H 57
F1 A 58
F2 B 58
f1 61
g1 61