6C-12 Power Assisted Steering System:
Scan Tool Data Definitions
Battery Voltage
This parameter indicates battery positive voltage.
TQS Power Supply (Torque Sensor Power Supply, V)
This parameter indicates the power supply voltage which
the P/S control module supplies to the torque sensor.
TQS Main Torque (Torque Sensor Main Torque, N⋅m)
The torque sensor is installed to detect the steering force
and the steering direction. It consists of two
potentiometers and the main torque sensor is one of
these.
TQS Sub Torque (Torque Sensor Sub Torque, N⋅m)
The torque sensor is installed to detect the steering force
and the steering direction. It consists of two
potentiometers and the sub-torque sensor is one of
these. Its output characteristics are compared with those
of the main torque sensor.
Assist Torque (N⋅m)
This parameter is an internal parameter of the P/S
control module. It is obtained by computing the torque
sensor input signal.
Motor Control (Motor Control Current, A)
Based on the input signal, the P/S control module
determines the assist amount and controls the current to
the motor suitable for that assist amount. This parameter
indicates that control value.
Motor Monitor (Motor Monitor Current, A)
This parameter indicates the actually measured value of
the current flowing to the motor. The motor circuit
condition is diagnosed by comparing this parameter with
“Motor Control” parameter described previously.
Vehicle Speed (km/h, MPH)
Vehicle speed signal is fed from BCM. P/S control
module determines the amount of power assist based on
this vehicle speed signal and the torque sensor signal.
Engine Speed (rpm)
Engine speed signal is fed from the ECM so that it can
be used for trouble diagnosis of the electric power
steering system.
Motor Volt (V)
This parameter indicates the voltage between motor
terminals.
Ignition switch (ON, OFF)
This parameter indicates the condition of the power
supply through the ignition switch.
Visual Inspection
S7RS0B6304007
Visually check the following pats and system.
P/S System Symptom Diagnosis
S7RS0B6304008
This section describes trouble diagnosis of the P/S system parts whose trouble is not indicated by the on-board
diagnostic system (self-diagnostic function). When no malfunction is indicated by the on-board diagnostic system
(self-diagnosis function) and those steering basic parts as described in “Steering Symptom Diagnosis in Section 6A”
are all in good condition, check the following power steering system parts which may be a possible cause for each
symptom of the steering.
Inspection Item Referring section
Battery Level, leakage, color “Battery Description in Section 1J”
Connectors of electric wire
harness
Disconnection friction “Intermittent and Poor Connection Inspection in Section 00”
Fuses Burning “Cautions in Body Electrical System Servicing in Section 9A”
Parts Installation, damage
Other parts that can be checked visually
Condition Possible cause Correction / Reference Item
Steering wheel feels
heavy (Perform “Steering
Force Check” before
diagnosis.)
Steering wheel installed improperly
(twisted)
Install steering wheel correctly.
Poor performance of torque sensor Check torque sensor referring to “Torque
Sensor and Its Circuit Inspection”.
Poor performance of P/S motor Check motor referring to “P/S Motor and Its
Circuit Inspection”.
Steering gear case assembly faulty Replace.
Poor performance of vehicle speed
signal from ECM
Check vehicle speed signal circuit referring to
“DTC C1121 / C1123 / C1124: VSS Circuit
Failure”.