Electronic Differential Lock (EDL)

Limited slip differentials are considered a compromise between a standard differential and a locking differential because they operate more smoothly, and they do direct some extra torque to the wheel with the most traction compared to a standard differential, but they are not capable of 100% lockup.

Traction control systems are also used in many modern vehicles either in addition or as a replacement of locking differentials. One example is that offered by Volkswagen under the name of electronic differential lock (EDL).

This Electronic Differential Lock is a limited slip differential imitation which is an electronic system that detects wheel spin via ABS sensors and applies brakes to spinning wheels. This results in the torque being transferred via open differentials to another wheel that has more traction.

For example, the system brakes the wheel that is raised in the air and spinning freely, and engine power goes to another wheel that is on the ground.

Reference:
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