Here’s a description of the steering motor / EPS (Electronic Power Steering) system used in a 2014 Perodua Myvi LagiBest (also known as Myvi second generation ''M600'', years around 2011-2017), including its issues and parts. If you want diagrams or part numbers, I can get those too.

What is it

• The ''LagiBest'' Myvi has an Electric Power Steering (EPS) system, rather than purely hydraulic. It uses an electric motor to assist steering rather than a hydraulic pump.  
• Steering mechanism type: rack-and-pinion with EPS assist.  

How it works (basic components)

The EPS assembly normally includes:

1. Steering column with torque sensor. The torque sensor monitors how much effort the driver is putting in (how much force or twist the steering column is under) and sends signal to motor control unit.
2. Electric motor (assist motor) which provides torque assistance, making steering easier especially at low speeds (parking, turning).
3. Control electronics: includes sensors (torque sensor, possibly angle sensors), wiring, ECU for EPS, and connector plugs. It manages how much assist is needed based on vehicle speed, driver input, etc.
4. Steering rack & pinion (mechanical part) converting rotational motion of steering wheel into lateral movement of front wheels.

Specifics for 2014 Myvi LagiBest

• Engine options: 1.3 L K3-VE and 1.5 L 3SZ-VE, both use EPS.  
• The EPS unit in Myvi LagiBest from years 2011-2017 carries part number 45510-BZ090 for the steering rack (this is the rack part; the steering motor and EPS column are related but not always sold as a whole with that rack).  

Known issues

There have been some known problems in certain batches of Myvi LagiBest:

• A recall / service campaign because of EPS fault: many Myvi units (mainly early 2011-2012 models) had issues where the EPS light on the dashboard would turn on, and drivers would experience ''heavy to turn'' steering or loss of power assist.  
• The cause was traced to leakage (from somewhere in the steering system) allowing fluid or moisture or contaminants to reach the connectors or electrical parts of the EPS motor / module, which causes short‐circuit or failure of the EPS control / torque sensor.  
• The diagnostic trouble code often shown in these faulty cases: DS2 code C1513 (''Torque Sensor excess deviation'') when checked with diagnostic tools.  

Part / Repair Info

• The steering rack (mechanical part) OEM part number: 45510-BZ090 for Myvi LagiBest 1.3 / 1.5 (2011-2017).  
• There are refurbished (''recon'') steering racks available. These include tie-rod ends sometimes. Warranty might be short (e.g. 3 months).  
• The EPS motor/column is also available (sometimes from ''half-cut'' or used parts) though condition and warranty vary.  

If you like, I can pull up detailed specs (motor torque, electrical ratings, wiring pinouts) for the 2014 Myvi’s steering motor. Do you want those?