Power Steering System (For Sedan) Fail-Safe Chart

Steering. Yaris. Ncp93, 131
Power Assist Systems. Yaris. Ncp93, 131

Power Steering System (For Sedan) -- Fail-Safe Chart


When a problem occurs in the electronic power steering system, the EPSwarning light on the combination meter comes on, and the ECU stops the steering power assist, maintains the amount of power assist constant, or reduces the amount of power assist to protect the system.

DTC No.
Malfunction
Fail-safe
C1511/11
C1512/12
C1513/13
C1514/14
Torque sensor malfunction
Assist force restricted
C1517/17
Torque sensor malfunction
Power assist stopped
C1524/24
Motor malfunction
Power assist stopped
C1531/31
C1532/32
Power steering ECU malfunction
Power assist stopped
C1533/33
Temperature sensor malfunction in power steering ECU
Assist force restricted
C1534/34
EEPROM abnormal
Assist force restricted
C1535/35
Steering wheel location data error
Power assist stopped
C1541/41*1
C1542/42*1
Speed sensor malfunction
Amount of power assist remains constant at speed of 70 Km/h (43 mph)
C1551/51
IG power source voltage error
Assist force restricted
C1552/52
PIG power source voltage error
Assist force restricted
C1553/53
Overvoltage at IG and PIG terminals
Assist force restricted
C1554/54
Power source relay malfunction
Power assist stopped
C1555/55
Motor relay malfunction
Power assist stopped
U0100
ECM communication error
Amount of power assist remains constant at speed of 70 Km/h (43 mph)
U0129*2
ABS ECU communication error
Amount of power assist remains constant at speed of 70 Km/h (43 mph)
-
Extremely high temperature in ECU
Assist force restricted until normal ECU temperature recovers
-
Power source voltage drop
Assist force suspended until voltage recovers
  1. *1: w/o ABS
  2. *2: w/ ABS
HINT:
The amount of power assist may be decreased to prevent the motor and ECUs from overheating if the steering wheel is continuously turned when the vehicle is either stopped or driven at a low speed, or if the steering wheel is kept at either full lock position for a long time. In such cases, the amount of power assist returns to normal if the steering wheel is not turned for approximately 10 minutes with the engine idling.