Screen black after battery change

[toffee_pie]

1 hour ago, ezpzDUDE said:

 

Would be great if Lexus knew this rather than charging a 4 figure sum to get it going?!

[rayaans]

15 minutes ago, toffee_pie said:

Would be great if Lexus knew this rather than charging a 4 figure sum to get it going?!

They do know this. They're not stupid. It doesn't work for when the unit is actually dead. 

[toffee_pie]

1 hour ago, rayaans said:

They do know this. They're not stupid. It doesn't work for when the unit is actually dead. 

Well that defeats the point then does it - why is the unit dead from a Battery change - seems you are ok with this? 

[rayaans]

43 minutes ago, toffee_pie said:

Well that defeats the point then does it - why is the unit dead from a battery change - seems you are ok with this? 

Faulty component. Like I said, Lexus heavily subsidise the unit. Mine happened when it was over 7 years old. Cost £500. The car didn't cost me anything further so I'm not massively fussed

[riki1479]

Rayaans, do you mind telling me if the new unit needing coding to the car or did it just plug in and work (exception of calibrating the camera). I am considering a second hand unit but the electrician said he wasn't sure if it would need coding and if it can be done so a bit of a risk me buying it hence asking here. Thanks

[Paul Brooksbank]

I've just changed my Battery and guess what? Screen dead, no sound but air con works. I've tried the reset described above to no avail. Anybody figured out what blows yet?

[rayaans]

2 hours ago, Paul Brooksbank said:

I've just changed my battery and guess what? Screen dead, no sound but air con works. I've tried the reset described above to no avail. Anybody figured out what blows yet?

Its the radio unit itself. Kills itself and the screen goes dead as the connections all go through the radio. 

Essentially requires a new radio unit to work which isnt cheap unless you get a second hand one

[toffee_pie]

Like I said multiple times, it's an issue with the radio unit itself - my guess as an established electronic engineering is that there's insufficient or no transient protection on the DC input to that unit - hence it blowing up when you replace the Battery. Lexus won't have any of this of course and want a complete unit - of course they do. 

There's a small claims court which is the route I would take in a situation like this, sometimes you need to stand up for your rights when you aren't getting anything from the manufacturer.

I've changed the Battery about 400 times in my Subaru and not once has anything blown, this has as many modules and so forth than a Lexus LS car, there's no reason why such a mundane task should cause such catastrophic damage 

[matt8]

This topic is the reason I’m never touching my 12v Battery again. Lexus can do it.

Sorry you got burnt, @Paul Brooksbank

[Paul Brooksbank]

This has really ****** me off. The thing is, how come you can connect a new unit to the supply without that one burning out? 

I'm going to speak to my cousin over the weekend, he's an electronics design engineer. Hopefully he'll find the problem and rebuild the offending board.

[ColinBarber]

1 hour ago, toffee_pie said:

my guess as an established electronic engineering is that there's insufficient or no transient protection on the DC input to that unit - hence it blowing up when you replace the battery.

That and possibly combined with ageing components as this only started to become an issue a couple of years ago.

[toffee_pie]

33 minutes ago, ColinBarber said:

That and possibly combined with ageing components as this only started to become an issue a couple of years ago.

It will have nothing to do with ageing components, if it's a design flaw that issue would have always existed but batteries aren't changed for about 6 or so years..

The easiest way to see what's happening is look at the circuit board and the supply input for the navigation, there's going to be a choke or a filter there and also tvs diodes which will prevent voltage transients damaging sensitive logic chips. If it's not present there isn't much you can do and hope that something as simple as a fuse is blown.

[ColinBarber]

3 minutes ago, toffee_pie said:

It will have nothing to do with ageing components, if it's a design flaw that issue would have always existed but batteries aren't changed for about 6 or so years..

Batteries are changed/disconnected all the time. The one on my old IS300h was disconnected on more than one occasion without issue.

[toffee_pie]

7 minutes ago, ColinBarber said:

Batteries are changed/disconnected all the time. The one on my old IS300h was disconnected on more than one occasion without issue.

They made proper devices back then it seems without cutting corners 

[ColinBarber]

Just now, toffee_pie said:

They made proper devices back then it seems without cutting corners 

It's the same model/pioneer audio unit that is giving problems here, just it wasn't 9 years old when I had it.

[toffee_pie]

14 minutes ago, ColinBarber said:

It's the same model/pioneer audio unit that is giving problems here, just it wasn't 9 years old when I had it.

I dont know about that - you know how electronic products work right, they have revisions or mod level changes - what is the same on the outside is not necessarily the same on the inside

[ColinBarber]

Yes. For this it's only one of the specific audio options and only occurs for the 2013/2014 vehicles when that specific model was in use, no info if this is common to just a specific hardware revision. However none of them started to fail until a few years ago. Some people in the states have managed to recover their units by performing a reset procedure which indicates at least in some situations it isn't a hard fault such as an internal fuse blowing.

[toffee_pie]

obviously there is something going on here - I suspect a hardware issue

[morg75]

From my own experience it also effects models from 2015 (I own a 65 plate). I suspect changing the Battery isn't the cause if the problem it just is the final straw. I would expect that something internal has previously failed causing the continual Battery drain. When you disconnect the Battery, the radio unit  discharges and damages something else internally. It is removing the Battery that allows it to finally fail rather than connecting a new one, because it has a protection circuit. I have disassembled a unit and found no obvious damage but I don't have circuit designs to analyse more. My advice, buy a secondhand unit (or a discounted new one) it didn't need recoding when I did it. Reporting another failure to Lexus GB may help others in the future.

[toffee_pie]

Lexus will most likely not entertain anything and deny there is anything wrong. How do you know there's protection on this head unit, unless you can decipher components and have a scheme it will be difficult. 

There could be a CMOS Battery used for the clock memory but that shouldn't prevent the unit going dead itself.

Lexus sell much more cars in the USA than England so I would trawl forums there to see what is happening 

[agent_dess]

@morg75 i thought the issue was only limited to 2013/2014 models.... Not yet heard of a 2015 having the issue but you seem to imply otherwise??

[morg75]

My radio failed in a 65 plate Fsport IS300H with the Mark Levinson Premium system( part number 86130-53M52). The garage tried convincing me it was the amplifier at fault and should pay £2000 to replace it, but it was non-refundable if that wasn't the fault. I was aware of this forum thread so declined their offer and bought a second hand head unit. I bought a slightly older model stereo (86130-53M42 from 2014) and swaped the front control panel which is  slightly different after 2015. Both units are made by Pioneer.

[matt8]

Is there a procedure which one can follow before disconnecting and/or reconnecting the 12v Battery, to avoid the dreaded black screen or dead unit?

[agent_dess]

I think you if you connect another Battery in parallel so that power is not lost during the Battery swap out.  Otherwise safest bet is go or Lexus and let them handle it.

[agent_dess]

1 hour ago, morg75 said:

My radio failed in a 65 plate Fsport IS300H with the Mark Levinson Premium system( part number 86130-53M52). The garage tried convincing me it was the amplifier at fault and should pay £2000 to replace it, but it was non-refundable if that wasn't the fault. I was aware of this forum thread so declined their offer and bought a second hand head unit. I bought a slightly older model stereo (86130-53M42 from 2014) and swaped the front control panel which is  slightly different after 2015. Both units are made by Pioneer.

That's quite annoying to hear and not impressed that by 2015 they still had the issue.  Also annoying have to replace parts in the car with older parts.