Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Variable Compression Ratio Actuator
FUNCTIONS WITHIN THE SYSTEM
The compression rate of engine is changed according to the signal from VCR control module.
INDIVIDUAL FUNCTION WITHIN THE SYSTEM
VCR actuator is operated according to the signal from ECM. The current angle of VCR control shaft 2 is fed back to ECM.
VCR motor
VCR motor
rotates VCR control shaft according to the control signal of VCR control module.
VCR motor rotation angle sensor
VCR motor rotation angle sensor send the rotation angle signal of VCR control shaft 2 to VCR CU. (This signal is utilized to drive VCR motor.)
VCR control shaft 2 rotation angle sensor
When Ignition switch is ON position, VCR control shaft 2 rotation angle sensor
reads the position of VCR control shaft 2. (Reading position is utilized as the trouble diagnosis for VCR motor rotation angle sensor.)
INDIVIDUAL OPERATION
VCR actuator is operated according to the signal from ECM. The current angle of VCR control shaft 2 is fed back to ECM.
COMPONENT LOCATION
The VCR actuator is installed to the engine left side.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.