3 FD - MDPS System structure Steering Column U/Joint MDPS SYSTEM MOBIS Power Head MOBIS LWR MTG BRKT Steering Gearbox COCKPIT MODULE CHASSIS MODULE MOBIS
4 FD - MDPS Components ASSY section view Motor ECU Worm Gear Worm Wheel Bearing Spring To column To U/Joint ASSY exterior Main Housing Anti-Rattle Spring Worm Wheel Torque Sensor Assembly ECU Motor Worm Shaft Assembly Bearing Oval Ring & Cover
5 FD - MDPS Control logic Active Return Yaw Damping Assistance Boost Curve Motor Command + Torque Angle VSS Torque Angle VSS Main input signals for the control logic Steering Wheel Torque Steering Wheel Position (Angle) Vehicle Speed
6 FD - MDPS Ignition Switch Signal Engine rpm Vehicle speed Engine Load SAS Warning information Output motor Steering Load CANCAN Steering wheel torque & position sensor : Built in column CAN connection
7 FD - MDPS Torque sensor LA A LA B Linear Array 128 pixel Narrow spoke disk wide spoke disk Index point
9 FD - MDPS ASP (Absolute Steering Position) calibration 1 When ? - MDPS Assmbly was replaced with new one or used one from the other vehicles. - MDPS ECM (TBD) was replaced with new one or used one from the other vehicles. - After wheel alignment adjustment.
11 FD - MDPS ASP (Absolute Steering Position) calibration 3 Detect or Not detect: Every IG off & on, this value will show detect or not detect depending on the steering wheel position. But it will get detect naturally as the steering wheel is rotated more than 180° while driving. (not detect does not mean the calibration fault.) CAL&INDEX: Calibration is OK and Index was found. After DTC detection, the angle value will be fixed by zero.
12 FD - MDPS ASP (Absolute Steering Position) calibration 4 What happen if it is not done? 1)In case of replacement with new part - Motor assist is available but warning lamp will blink and active return (on-center control) will stop. 2) In case of replacement with used part - Motor assist is available and warning lamp will not turn on. Active return (on-center control) will stop. What happen if it was done with wrong way? (improper steering wheel center position) - You may have DTC (C1259) without warning lamp on. However, the motor assist is available but the active return (on-center control) will stop.
14 FD - MDPS Power supply & Relay Motor relay (built in motor) ECM relay (built in ECM) - Every ignition off from engine running, the relay will sound (off) after 2 3 seconds. - However, if you turn the ignition on before 2 3 seconds, the motor assist is available under the ignition on condition even though the engine is not running.
15 FD - MDPS Overheat Protection (Derating motor current ) - Before the DTC(C1603) is detected (before the temperature reaches 85°), as soon as the steering torque reaches to maximum value, the motor current will decrease by 40% immediately in order to prevent the overheat in the system in advance.
17 FD - MDPS Failsafe for vehicle speed signal fault - The vehicle speed signal comes from PG-B in A/T through PCM(or TCM) and CAN. (Non-OBD only) - Warning lamp OFF, No DTC and Motor ON (Default vehicle speed is 40km/h) Normal conditionPG-B open circuit
18 FD - MDPS Failsafe for IGN1 signal fault Failsafe for engine speed signal fault For example, disconnect the CKP sensor while driving and confirm the symptom. - Warning lamp ON (IG On condition), - No DTC - Motor assist ON for 60 seconds and turn off for the safety.
19 FD - MDPS Warning lamp 1) Warning lamp ON + Motor stop: Critical fault - Torque sensor fault - Motor or Relay fault - MDPS ECM internal fault - IG signal fault (from next power cycle) - Battery voltage low or high 2) Warning lamp ON + Motor assist: Minor fault - CAN related faults 3) Warning lamp OFF + Motor assist: Minor fault - ASP calibration failure - Variant coding fault - Vehicle speed signal fault