Hey everyone — posting this because I’m honestly shocked this happened on a basically new vehicle and I’m trying to see how widespread this is.

I have a 2023 Land Rover Defender 130 (bought brand new). It’s been to the dealer more times than it should ever need to be for a newer vehicle.

Latest issue:

We’re traveling with my family (I’m from MA, currently stuck in NY) and I woke up to the dash warning:

“STOP SAFELY – ELECTRICAL FAULT”

Within moments the truck completely died in the street with my family in the car. No limp mode, no “get to a safe location”… it was basically dead / disabled right there. Had to get it towed and now it’s sitting at a dealer in NY. They’re telling me it may not even be looked at by a tech until Monday, which is brutal because we’re supposed to head home.

I’m seeing a lot of posts mentioning the P400 DC/DC converter and similar “Stop Safely” warnings — curious if this is what I’m dealing with too.

For context (this isn’t the first major issue):

• Recently had a coolant loss / no coolant situation — dealer said it was O-rings going into the turbo
• Previously had to replace all upper coolant hoses
• Had a scary situation where the steering wheel wouldn’t turn at all until I disconnected the negative battery terminal to reset the system
• Also had the heated steering wheel burn a hole through the wheel and burn my hand while driving (replaced under warranty)

At this point I’m beyond frustrated — but more than that, I’m concerned this is a serious safety defect if these trucks can just shut down in traffic with a “Stop safely” message.

Questions for anyone who’s dealt with this:

1. Did yours end up being the P400 DC/DC converter or something else?
2. Any common fix / TSB / part backorder issues?
3. Did the dealer replace the converter, battery, or wiring harness, alternator?
4. Anyone have this happen more than once?

even my recent o-rings in the turbo that needed to be replaced… just find myself wondering “how long till it happens again?”Appreciate any insight. I’ll update once the dealer diagnoses it.

 

Just wanted to provide an update -
I am now on Day 3 without a car. My truck is stuck in NY and I am in MA.
Neither dealership (Huntington NY nor my JLR Sudbury in MA) have loaners for me.
I have been told to talk with corporate.
Corporate said I have to pay out of pocket for a rental and submit for review and reimbursement once my truck is returned to me.
I am still with my family member's car who lent it to me in NY so I could get my family home.
I have to figure out logistics now of getting them their car back, getting a rental, and figuring our next steps, as they are not being very helpful.
I am actively reviewing lemon law, as I have never had a new truck with so many issues. Sad.

 

I think the lemon law route might be your best option. The Defender has a pretty good track record for reliability, but it seems like yours is an unfortunate exception. Are you still under warranty?

 

To be honest, a MY23 is hardly a 'new' car and also I would suggest you check the lemon law before throwing it around. From the limited info it certainly does not seem you will get any traction this late into the game at a dealer.
And I think you should prepare yourself for anywhere between a few weeks to months for getting a new DC-DC converter.
You always have options though. Keep being a hostage to this car, or just trade it for a new one?

 

Just a thought, have you considered trying to source the DC to DC converter yourself from online parts retailers or salvage houses? I haven't done the job myself but it seems that this is a relatively simple part to replace.

https://www.jaguarparts.com/oem-part...rter-433123464

If you do go this route, I would go ahead and send the receipt to JLR as a warranty claim.

 

I purchased it brand new then. It is still under warranty. It has been back at the dealer multiple times every year since day 1. Constant problems.

 

Unfortunately lemon law in MA is one year or 15k miles for a new car purchase. As yours is over 3 years old, that won't apply

Lack of a loaner is shocking if you bought the car new from them they usually help with that - or can rent a vehicle for you on their dime

Most important is getting the issue fixed. Sounds like that will be done in NY where the car now is? Any indication of timescale for that?
Puzzling that you have had so many seemingly unrelated issues. As overall reliability of these seems to be very good

Would push the dealer to dig deep on the diagnostics.