Do Not Sell My Personal Information Jump to content


New NX350h unresponsive / no start. Thoughts?


Recommended Posts

New NX350 owner. Picked up this lovely car on Tuesday (3rd). All good. Next couple of days took the car out – all good.
Thursday (5th) went to the car, with key fob. Grasped door handle to open door as usual but door didn’t open. Got in car by using the button on the key fob, sat down. The car dash welcomed me “Welcome <MY NAME>” (which I hadn’t seen before (???)), I put seatbelt on, the seat & steering wheel swung automatically into my preferred position.
I pressed power button, but the car didn’t start. It displayed “press brake, and press power button to start” message but no start!
After a few seconds, the dash went blank. 
I could use other electronics (seat position, electronic door open, interior lights etc) but other than that the car is not doing anything.
I got out (seat & steering wheel auto retracted as expected) and had to again use the fob buttons to lock the car.
Same experience over the next hour.
Eventually, I got in, sat down, HELD the keyfob up against the Power button, held the brake pedal down and then pressed power.
The car started normally.
I drove it and was able to lock it, unlock it, open the boot with foot gesture etc etc – all normal. Next day all still normal...
Any thoughts about what was/is going on?
I rang the dealership & the service manager reported he thought some problems with Lexus Link and advised me to remove my vehicle from the Lexus app.
(Note, I only have one key fob as per other reports of keyfob shortage or I would have immediately tested a second keyfob)

Link to comment
Share on other sites

6 minutes ago, JP56 said:

Thanks for the advice (& the welcome!).

I have new spare CR2032 batteries. Is there any downside to changing it myself? Thanks

No downside, did mine spare fob  yesterday, takes 2 minutes. if your not sure how to do it you tube will help.

  • Like 2
Link to comment
Share on other sites


I wouldn't rule out operator error. Having had my car for a year now, there has been the odd occasion when I have received the same initial message. Basically, I thought I had my foot on the brake with the initial press of the button but, in reality, my finger was marginally quicker than my foot. Should no problem, the dash tells me what to do, but if I inadvertently get the timing wrong and double tap the start button, nothing happens. 

In my 450, and possibly your 350, the engine doesn't start so there is no audible cue that the car is ready to go. There is a Ready indicator on the dash but after years of low tech motoring, I still don't instinctively look for this. Usually, I move the gear lever and if Drive or Reverse lights up, I know the car is ready. If it doesn't light up, I check the dash panel. Usually it says, 'idiot behind the wheel, get a grip'. Or something like that to give me a clue. Maybe it's just me ...

  • Like 3
Link to comment
Share on other sites

58 minutes ago, Harrier Man said:

I wouldn't rule out operator error. Having had my car for a year now, there has been the odd occasion when I have received the same initial message. Basically, I thought I had my foot on the brake with the initial press of the button but, in reality, my finger was marginally quicker than my foot. Should no problem, the dash tells me what to do, but if I inadvertently get the timing wrong and double tap the start button, nothing happens. 

In my 450, and possibly your 350, the engine doesn't start so there is no audible cue that the car is ready to go. There is a Ready indicator on the dash but after years of low tech motoring, I still don't instinctively look for this. Usually, I move the gear lever and if Drive or Reverse lights up, I know the car is ready. If it doesn't light up, I check the dash panel. Usually it says, 'idiot behind the wheel, get a grip'. Or something like that to give me a clue. Maybe it's just me ...

It is the same with the NX300h - if you are too quick things go wrong. Warning buzzers, lights and messages - it is usually an operator error! I now look for the Ready light to illuminate! The car prevents you from doing things for a reason - though I do not always agree!

  • Like 5
Link to comment
Share on other sites

Thanks for the input. I'm 100% certain I am doing things in the right order - no 'too quick' actions. 

It's as I reported in OP. 

I'm coming to conclude that the fob (fob Battery?) is the potential problem source.

I hope Lexus come up with Key #2 rapidly

Can one BUY a spare fob?

  • Like 1
Link to comment
Share on other sites

I doubt it is the key Battery because it shouldn't be old enough to have gone flat, it would have warned you if it was getting low and the use of the fob buttons would use more power than the smart entry system.

I suspect there was some external RF interference stopping it working correctly, or the smart entry ECU wasn't functioning correctly (software bug?) and then reset itself. Certainly nothing to do with Lexus Link.

If it happens again try moving the vehicle just a few metres and then testing again.

  • Like 2
Link to comment
Share on other sites

18 hours ago, ColinBarber said:

I doubt it is the key battery because it shouldn't be old enough to have gone flat, it would have warned you if it was getting low and the use of the fob buttons would use more power than the smart entry system.

I suspect there was some external RF interference stopping it working correctly, or the smart entry ECU wasn't functioning correctly (software bug?) and then reset itself. Certainly nothing to do with Lexus Link.

If it happens again try moving the vehicle just a few metres and then testing again.

I Usually Get a Warning on the Info screen That the key fob Battery is low and i should replace it...!!!

  • Like 1
Link to comment
Share on other sites


One difference we have found between the NX300h and the NX350h regarding the smart keys is that the range of the new types seems less than the old model. Whether this is due to the key itself or the receivers in the car is unclear.

For example, if my other half leaves the key (we only have one!) in her handbag and puts the bag in the rear footwell we often get "key not detected" on the dash. Putting the bag on the rear seat seems fine.

  • Like 1
Link to comment
Share on other sites

2 hours ago, malcolmw said:

One difference we have found between the NX300h and the NX350h regarding the smart keys is that the range of the new types seems less than the old model. Whether this is due to the key itself or the receivers in the car is unclear.

For example, if my other half leaves the key (we only have one!) in her handbag and puts the bag in the rear footwell we often get "key not detected" on the dash. Putting the bag on the rear seat seems fine.

The new keys use Ultra Wideband (UWB) which allows for much more precise distance control, and stops relay attacks too.

  • Like 1
Link to comment
Share on other sites

17 hours ago, Ken R said:

From what you are reporting I reckon there is almost certainly a malfunction with the key. 

My conclusion as well... Shame the current situation prevents a test. Hope Lexus rock up with a 2nd key soon. Others waiting on a 2nd key? How long you been waiting?

  • Like 2
Link to comment
Share on other sites

I'm seeing references to '12v battery' in this thread.

So, the NX hybrid has TWO batteries (putting aside the EV mode Battery power) - one for 'electronics etc, and one for starting the car ...  put simply... :-)  and the 12v Battery reference is to the 'electronics' Battery that may have been at fault in my OP???

Any clarification welcomed!

Link to comment
Share on other sites

2 minutes ago, JP56 said:

I'm seeing references to '12v battery' in this thread.

So, the NX hybrid has TWO batteries (putting aside the EV mode battery power) - one for 'electronics etc, and one for starting the car ...  put simply... :-)  and the 12v battery reference is to the 'electronics' battery that may have been at fault in my OP???

Any clarification welcomed!

Two batteries including the traction (EV) Battery. The 12v lead acid Battery (aux battery) that powers the car when not in ready mode and the large hybrid (traction battery) that takes over from the aux Battery when in ready mode. The vehicle is started by the traction Battery
 

You have no issues with either the two vehicle batteries,  nor the Battery in you key fob. 

  • Like 1
Link to comment
Share on other sites

1 hour ago, ColinBarber said:


 

"You have no issues with either the two vehicle batteries,  nor the battery in you key fob. "

Yep, having slept on this, I suspect that the ECU was somehow sidelined by something, and my physically starting the car by holding the fob up against the power button & driving it successfully reset it? Modern tech ... digital tech once latched into an 'error' state needs to be reset - we see it in IT all the time. 

Like you, I now think the batteries in play were / are all good.

I do wish I had the traditionally provided 2nd fob, though, just to eliminate the fob...

  • Like 1
Link to comment
Share on other sites

7 minutes ago, ColinBarber said:

Indeed. Keep hounding your dealer to supply this.

My 450h+ was manufactured mid December 2022 (arrived in UK February 2023), I purchased the vehicle (cancelled order) in June this year with one key. Second key was supplied at the begining of August. I think the car manufacturing date may be how Lexus are prioritising it.

  • Like 1
Link to comment
Share on other sites

4 minutes ago, Hayzee said:

I think the car manufacturing date may be how Lexus are prioritising it.

Exactly, as a letter from Lexus CS, posted in another thread stated. Lexus are going in production date order.

Hounding one's dealer isn't likely to achieve much, the dealers can't get the keys except through Lexus..

  • Like 3
Link to comment
Share on other sites

How odd. I can't say I've had that issue as of yet - thankfully. Knowing my luck, something like that would happen to me miles away from home! To me from the way you describe it, as already suggested, that sounds more like a key/immobiliser in key issue than the actual car. Especially if all has been well with the car ever since... One of my work colleagues has a Vauxhall Astra 

The only slightly odd situation I have is that occasionally if I start the car and go into drive or reverse too quickly, it doesn't 'load' my phone settings and I end up having some sort of blue screen with white writing on (not really looked too hard to see what it says to be honest) and one of those square QR codes. If I stop the car, put it into park, all of a sudden it'll then connect to my phone and all is well again. It won't do this unless I put the car back into park. My own way around this is to basically start the car as soon as I get in before doing anything else, to give it a few extra seconds 'loading time' as it were...

Over the last week or so, it's twice shown my "phone cannot connect to wireless". Not as quickly as the above situation, but about 2/300 yards into moving away. I'm confident this is more of a problem to do with my phone than the car though - as I do know it occasionally 'derps out' if I try to play music from it and it simply won't load anything at all. I had this very same issue in my two previous cars. It'll work great for a while and then for several months, for reasons unknown, it just won't load any music when you go into 'media'. Then at some point it'll start randomly working again only to 'break' again a few days later... Rince and repeat... Luckily, I don't listen to much in the way of music anyway! 

On 10/8/2023 at 1:00 PM, ColinBarber said:

Indeed. Keep hounding your dealer to supply this.

I've not rebuilt my strength enough to start pestering them again to be honest. I'm not sure how long to leave it before I start doing it with mine. I only collected my car just over a month ago, so I suspect it's nowhere near ready. I thought about giving them six months or so to give them a chance but, knowing their track record of keeping in touch/updates (i.e - non-existent), I suspect I was forgotten about the moment I drove away from the car park.

  • Like 1
Link to comment
Share on other sites

Latest Deals

Lexus Official Store for genuine Lexus parts & accessories

Disclaimer: As the club is an eBay Partner, The club may be compensated if you make a purchase via eBay links

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share






Lexus Owners Club Powered by Invision Community


eBay Disclosure: As the club is an eBay Partner, the club may earn commision if you make a purchase via the clubs eBay links.

DISCLAIMER: Lexusownersclub.co.uk is an independent Lexus forum for owners of Lexus vehicles. The club is not part of Lexus UK nor affiliated with or endorsed by Lexus UK in any way. The material contained in the forums is submitted by the general public and is NOT endorsed by Lexus Owners Club, ACI LTD, Lexus UK or Toyota Motor Corporation. The official Lexus website can be found at http://www.lexus.co.uk
×
  • Create New...