General Description
Speed sensor, located at speedmeter driven gear of transaxles, applies the principal of Hall-effect. As output shaft of transaxle rotates, the rotation of rotor, which is inside the sensor, generates Hall-effect and outputs a digital pulse. EPS CM detects vehicle speed, based on digital pulse signal, and controls solenoid valve current which controls driving force of steering wheel.
DTC Description
This DTC code refers to open/short of vehicle speed sensor circuit, or related system. EPS CM sets this DTC code and controls steering wheel operation power if engine rpm is too high while vehicle speed is "0".
DTC Detecting Condition
Item | Detecting Condition | Possible cause |
DTC strategy | Signal check
| Open/short in power circuit
Open/short in signal circuit
Open in ground circuit
Contact resistance in connections.
Faulty circuit to use VSS
Faulty sensor
|
Enable conditions | IG "ON"
|
Threshold value | Vehicle speed 0 kph & engine speed
= 2500 rpm (Engine speed after starting during 5 min = 4000 rpm permit) |
Diagnosis time | 20 sec
|
fail safe | Motor : Same with 255kph
Relay : ON
Fail lamp : OFF
Restoration condition : Power "OFF" or vehicle speed > 5 kph
|
Schematic Diagram
Signal Waveform
Fig.1) Driving : Vehicle speed sensor output 8.0~12.5V(HIGH SIGNAL) or 0.2~0.5V(LOW SIGNAL), as the vehicle moves, the 50% of digital duty wave is ouput. ( As vehicle speed increase, Hz increase)
Fig.2) Engine RPM signal at idle (TPS PWM)
Fig.3) Engine RPM signal at acceleration (TPS PWM)
Hz is 2 pulse / 1 rev, signal high is Approx. 3.5V more than, low is Approx. 1.0V less than. Also it must increase together if vehicle speed increases.