Hi. P400e, 2 years old and covered 40k - brakes failed recently when moving off on my driveway. I rolled into the road but luckily no traffic was coming as it was late at night. When pressing the brake pedal, there was an electrical squealing noise and after a few seconds various warning lights came on the dash. There was no brake control at all apart from when the car had almost crawled to a stop, where a full stamp on the pedal seemed to lock the brakes on. At any speed above crawling there was no chance of stopping. Very worrying for a 2 year old car. The AA rescue (via Land Rover Assistance) came out, phoned an on call technician who told him to disconnect the supplementary battery in the boot, then reconnect and this would temporarily remove the fault but it would come back at some point! I stopped this and said the car needed to go to the dealership and it was collected the next day. Ended up with an Enterprise hire car that's nowhere near big enough for what I need, no communication from the dealership other than 'someone will ring you back', and the wife said she doesn't trust the car so wont drive it when it comes back to us! Here's the info from the breakdown report:
Patrol found the following fault code/s:System : ABS - 9M6 / ESP 9.0.1 Status :U04B5 - Communication with the system <Brake>. Error Message : Invalid data from node. Error sporadic. Status :U01B4 - Communication with the system <Brake>. Error Message : Missing message. Error static.Brakes not working. Juddering when pressing. Warnings on. Booked truck for tomorrow. Hire car booked.Engine Oil Level Ok

I heard the on call technician say this is something he's seeing on 3+ year old cars, so was surprised it'd happened to mine. Sharing this so other owners can possibly get their cars checked and avoid a potential catastrophe.
Cheers

https://www.rangerovers.net/threads/hi-fro...st-2372076 2023 P440e SE Dynamic on order -cancelled

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I recently experienced a serious safety issue with my Range Rover and wanted to understand if it was just my car or something wider. After doing some digging, I’ve found multiple posts across forums describing exactly the same braking failure — this seems to be a widespread and very dangerous problem.

In my case, I was nearly killed in an accident. While trying to stop at traffic lights, I hit the brakes and the pedal pushed back into my foot. For 1–2 seconds, there was almost no braking. I ended up in the junction — almost hit broadside by a truck, with my wife and kids in the car.

An expert looked into the issue and confirmed it's a known design defect. Land Rover knows about it. It relates to the auxiliary battery — when that battery fails or voltage drops, it doesn’t trigger a proper warning, and in that state, it interferes with the system that switches from regenerative to hydraulic brakes. In those moments, the braking effectively fails.

I’ve been advised to report this to the DVSA (UK regulator) using this link:

https://www.gov.uk/vehicle-recalls-and-faults/report-a-serious-safety-defect

— the process took less than 10 minutes.

In my case, the conclusion was clear: the car does not meet safety regulations in its current form. And it’s not the only JLR vehicle affected — the I-Pace had to be recalled globally for a very similar issue.

So if you’ve had even a single episode like this — please report it. It’s likely a matter of time before it happens again. All of these cars will eventually degrade, and the fault could return. Land Rover won’t act unless forced to — but if enough people report the issue, DVSA will force a recall and fix.

Please — it only takes 10 minutes. Report it. It could save someone’s life.