Power Steering System (W/ Vsc) Fail-Safe Chart

  1. FAIL-SAFE FUNCTION

Power Steering System (W/ Vsc) -- Fail-Safe Chart


If a problem occurs in the power steering system, the power steering warning light in the combination meter comes on and the power steering assist is stopped, locked at a particular point or decreased simultaneously to protect the system.

Power Steering System
DTC Code
Detection Condition
Fail-safe Operation
C15F0
Short circuit between power steering solenoid valve terminals SOF+ and ground
Assist force is restricted.
Short circuit between power steering solenoid valve terminals SOF- and ground
Power assist continues as normal.
Short circuit between power steering solenoid valve terminals SOF+ and SOF-
Assist force is restricted.
Power steering solenoid valve open circuit
Assist force is restricted.
C15F1
Steering angle sensor circuit malfunction
The power steering system is limited depending on which ECU has lost communication. For details, refer to Fail-safe Function.
C1541
Vehicle speed signal malfunction
C1544
Engine speed signal malfunction
U0100
Lost communication with ECM/PCM "A"
U0126
Lost communication with steering angle sensor module
U0129
Lost communication with brake system control module

FAIL-SAFE FUNCTION
If the power steering ECU cannot receive the steering angle signal, steering zero point memory, vehicle speed signal or engine speed signal, the power steering warning light in the combination meter illuminates and the vehicle enters fail-safe mode.

Malfunction Area
Fail-safe Mode
Steering Angle Signal
Steering Zero Point Memory
Vehicle Speed Signal
Engine Speed Signal
X
-
-
-
  1. V-Q control fixed
  2. Steering angle compensation disabled
  3. Steering wheel return compensation disabled
  4. Engine speed compensation normal
-
X
-
-
  1. V-Q control normal
  2. Steering angle compensation disabled
  3. Steering wheel return compensation disabled
  4. Engine speed compensation normal
-
-
X
-
Assume vehicle speed 40 km/h (25 mph) and control each compensation
-
-
-
X
  1. V-Q control normal
  2. Steering angle compensation normal
  3. Steering wheel return compensation normal
  4. Engine speed compensation disabled
X
X
-
-
  1. V-Q control fixed
  2. Steering angle compensation disabled
  3. Steering wheel return compensation disabled
  4. Engine speed compensation normal
X
-
X
-
Constant fluid volume
X
-
-
X
  1. V-Q control characteristics fixed
  2. Steering angle compensation disabled
  3. Steering wheel return compensation disabled
  4. Engine speed compensation disabled
-
X
X
-
  1. V-Q control fixed
  2. Steering angle compensation disabled
  3. Steering wheel return compensation disabled
  4. Engine speed compensation normal
-
X
-
X
  1. V-Q control normal
  2. Steering angle compensation disabled
  3. Steering wheel return compensation disabled
  4. Engine speed compensation disabled
-
-
X
X
  1. Assume vehicle speed 40 km/h (25 mph) and control each compensation
  2. Engine speed compensation disabled
-
X
X
X
  1. V-Q control characteristics fixed
  2. Steering angle compensation disabled
  3. Steering wheel return compensation disabled
  4. Engine speed compensation disabled
X
-
X
X
Constant fluid volume
X
X
-
X
  1. V-Q control characteristics fixed
  2. Steering angle compensation disabled
  3. Steering wheel return compensation disabled
  4. Engine speed compensation disabled
X
X
X
-
Constant fluid volume
X
X
X
X
Constant fluid volume
HINT:
X: Malfunction