Thread: Rear e-diff won't engage

Originally Posted by Micha

Just out of curiosity: are you sure about that, for dry tarmac and when not slamming it?
I mean I never saw in the UI the lock engaging (changing from green) in such circumstances.
Also many D4s do not even have a rear diff lock.

Other D4 not having one has no bearing on what a d4 with one does. That just silly thinking.

If G say it locks for takeoff I’d believe him as he’s very knowledgeable however right to ask for justification

My son monitored live values which revealed that the e-diff is pre-armed for possible wheel-spin and for lots of other circumstances too.

End of story (I presume, that is):
Genuine part part was sourced from Rimmer Bros at £437, and replaced at a local indy who has the needed calibration aparatus.
Original diff lock motor turned out to be seized.
First day out in the desert, the diff lock worked flawlessly.
Thank you guys for your helpful guidance.

Good that it's working again.

My MY21 L405 has a display that shows the extent of each of the rear and centre diffs locking, with a circle that is partly red indicating the percentage locked. Even very gentle straight-line acceleration on a sealed road shows the rear diff 100% locked up to about 70 kph and the centre diff starting at about 50% then gradually reducing to nil.