Ls 400 - Its Getting Worse - Some Wisdom Needed Help !

[harrylime]

posted the other day about my ls400 not starting. It appears to be the solenoid contacts or starter. Went out today just to see if it would start, it did. Decided to take it around the block just to keep it moving, while it was running. After a hundred yards or so dashboard lights came on- check engine and vsc off. At the same time I lost all throttle response. The engine was running at idle speed. I stopped and put it in Park and the engine started racing 1500 rpm or so. I stopped the engine and restarted it and nervously drove it the few hundred yards home, during which time it seemed fine.

I got one of these instead of a Jag because of perceived reliability. I am starting to lose faith now and once I lose faith in a car, it's gone. It may be something simple- but has anyone experienced this before?

[Tulpen]

It sounds like it could be the Battery. These cars are very sensitive to low Battery voltages.

[n4chv]

Really sorry to be reading about your experience. I owned my LS400 for over 13 years and 225k miles - without question it is still the most reliable I have ever owned. My current LS430 is also a superb car however it has not been entirely fault-free like my previous LS400. I put this down to the additional gadgets and technology but thankfully it's all fine and running wonderfully.

I don't know how often you use your vehicle but as Brian has said in his post, these cars can be sensitive to low Battery voltages and if your car hasn't been used much this could explain some of your issues.

If you have a good local mechanic / auto-electrician, I am sure they would be more than capable of giving the car a good checkover.

During my own ownership period, I did leave the car parked up for almost 3 weeks without any use in the middle of a very cold spell. The car did start although the Battery sounded like it was struggling to turn the engine over. I initially had a few warning lights come up on the dashboard including the VSC lights amongst others.

After a few miles of driving, the car drove fine and I stopped the car and re-started and there were no warning lights.

I hope you can / do get your car sorted and back into full working order and that more importantly, your faith is restored

[ambermarine]

Hugh

Are you leaving the car on Battery management charge when not in use The Mark 4 is notorious for running the Battery down on prolonged periods? say 10 days without use.

The throttle is electronic on the Mark 4 it was changed to that on the vvt-i engine launch.

The choke will run the engine initially at about 12-1500rpm until it is about halfway to running temprature

If you are running on low amperage starts the ECU may be getting spikes whilst the alternator is taking up the strain recharging the Battery,all power systems are served by the Battery not the alternator

Get a fully charged Battery installed and see which of the malfunctions re-occur .

The problem with the starter could also be a symptom of a weak Battery.

[cruisermark]

harry i think you are worrying needlessly - these cars are pretty reliable and faults like this are rare and easily sorted - as the guys above have pointed out it could be a Battery - get that checked out - and then get your starter fixed - but dont make any hasty decisions - im sure it will get sorted in the end and the car will look after you

[harrylime]

I replaced the Battery around 10 months ago, with one from a Lexus garage. When it failed to start (around a week without use), I charged it on trickle with my CTEK charger. It would only click but not start. It is now showing 12.3 volts. It will not help that I keep going out to try it to see if it starts. It has, around half a dozen times. What befuddles me is having two apparent faults at the same time. Failure to start, with just a click, and then the check engine and VSC lights coming on / with total lack of power (I was not aware of the limp home mode so did not try the gas pedal all the way down).

At the moment it is starting every time, so not sure what to do. I had resigned myself to having the starter out, but that has disappeared for now. I have removed and cleaned every fuse in the main fuse box, as I recall someone else trying that.

[Tulpen]

If you haven't used it for a while, the Battery drains very quickly. There are threads on here about solar trickle charges which some guys have fitted.

The other thing that I've had is that, after servicing.....where the Battery was removed, the mechanic didn't tighten the Battery terminals well enough. I kept getting these weird indications as one of the terminals loosened off even more.

I suggest you check the terminal connections then, as Nach suggests, get an auto electrician to check the Battery out.

These really are great cars and I'm sure you'll love owning one.

[Titch LS]

Hugh, once or twice I've experienced the exact same symptoms as yours on my mk4. It has always been due to low Battery voltage. I know your Battery is only 10 months old but if it has ever been substantially discharged (for any reason) in that time, it will affect its ability to hold a charge well in the future due to sulphation in the cells. These cars call for a very healthy Battery as they are very sensitive to voltage drops. It will need a good charge and at least a 10 mile run. It might even sort your starter problem as it could be related. Low voltage brings on weird electrical gremlins. I had a load of electrical problems on a Rover Sterling once and all was cured with a new Battery.

[harrylime]

Brian

Many thanks, you could be right. As I said I have had it charged, but perhaps she needs a good run. It will be a slightly nervous one, half expecting a starting problem or the car going into limp mode. we'll see.

[Cotswold Pete]

At 12.3 volts your Battery is barely 50% charged, and so if you have been trickle charging and it's only got this far, I would say the Battery has a faulty cell at the very least.

I would get a proper load check done on it. A Battery at 12 volt is considered to be less than 10% charged.

Also as soon as you try to start the starter motor is probably dropping the voltage by another 0.5 volt, which will tell the ECU, no juice here to do anything.

However there is going to be enough to sort of power up bits and pieces which is why your dash is sort of showing random stuff.

What you describe I had on my Mk4 3 months ago, and the Battery was only 2 years old and out of guarantee.

I would have said your Battery is still under warranty, so a new one should be no problem.

You might also want to get the alternator checked over, as if it is not totally spot on with charging it can cause Battery to fail earlier than usual (but this is rare IMHO)

[n4chv]

I did purchase a Battery from Lexus and after 2 and a bit years, I had some electrical gremlins including a couple of times when I would turn the key in the ignition and it would be completely dead and I'd then try it later and it would start without any problems

When the car went in for a service, the dealer told me there was an issue with one of the Battery cells and they replaced the Battery FREE OF CHARGE - the dealer said they offered a 3 year warranty on batteries. I thought it was only 1 or at best 2 years so good result for me.

The Battery only cost me £90 which seemed more than reasonable from a Lexus dealer

[harrylime]

It has started now half a dozen times without problems., went out today and drove it around the block. It seemed fine except for my dash lighting (indicator needles etc) going out for a few seconds. If it turns out to be the Battery it will be a right result, because I had resigned myself to a new starter at close to £700

[brucey72]

As Pete said 12.3 volts is actually quite a low charge. Isn't it supposed to be around 12.7 volts or something for a full charge?

[plastic orange]

First cold day yesterday and Lexus wouldn't start due to low Battery. Charged it up and it started, but same again today. Fortunately my Battery has a 5 year warranty (Bosch silver), so I'm awaiting delivery of a replacement. It had lasted around 31/2 years, so not too bad really these days. However, I have a 12 year old Battery on my V8 Morris Minor which still holds it charge.

Pete

[harrylime]

I just checked the voltage with the engine running and it was 14.3 volts. Hopefully that means the alternator is OK. It could be a faulty Battery cell, I will get it checked

[n4chv]

During the 15 years and 230k miles on my LS400, the alternator never needed replacing - when I sold it last year, the car was on it's 4th Battery and apart from 1 Battery which had to be changed after 2 and a bit years, I got 4 or 5 years out of each Battery

My LS430 has a lot more gadgetry which relies on the Battery but then again, as long as I use the car on a regular basis I would still expect the Battery in this to give me 3 or 4 years at least.

[Cotswold Pete]

As Pete said 12.3 volts is actually quite a low charge. Isn't it supposed to be around 12.7 volts or something for a full charge?

12.6 volts is what you have with 100% charge. so the margin is quite small.

I think the problem is that lots of small trips kill a Battery, because when you kick over the starter motor it causes electrolyte build up on the plates, and then the process of the alternator re-charging removes the electrolyte build up ( I did find a video on Google a while back - but cannot find it now). However if you do not manage to remove all the chemicals off the plate, they build up, and once you get the plates being connected by a build up, then you have a cell failing (shorted).

Because the Lexus has systems running 24/7 then overnight you are helping the Battery to build up the bad stuff on the plates.

At least that is how I read it when I did some research, but stand to be corrected if someone knows more about the chemistry of it all.

When I did nothing but long drives every day, I would find a Battery lasting well over 5 years (and that was in the days when they would only give a 2 year warranty).

[SlowV6]

Off topic sorry, but I did enjoy this sentence..

"However, I have a 12 year old Battery on my V8 Morris Minor which still holds it charge."

I bet that is most amusing.

[ROYT]

Get a new Battery before you pay out for the starter.

Sounds to me like Battery problems all the time, starter may be OK

The Battery on my series two LS is a 2008 YUASA, still perfectly OK

[Mybikes a cx500]

I just checked the voltage with the engine running and it was 14.3 volts. Hopefully that means the alternator is OK. It could be a faulty battery cell, I will get it checked

Sounds like a dodgy Battery to me

[Cotswold Pete]

Off topic sorry, but I did enjoy this sentence..

"However, I have a 12 year old battery on my V8 Morris Minor which still holds it charge."

I bet that is most amusing.

I have car batteries for other projects, over 8 years old, and no problems.

The Morris Minor ignores it's Battery when not left at night. This was the reason in the good old days, my dad used to run a cable out of the house to a parking light he hooked up to the window of the car. If had used his car Battery, he would have had the same issue that we Lexus owners now have with the security systems working 24/7.

Maybe a doberman would be a better bet, leave it in the LS overnight, disable all the electronics and see if anyone dares steal anything!!!

[harrylime]

Been out again for a 15 mile run, and it's running like a Swiss watch. I'm starting to regain confidence and belief that it really is just very sensitive to voltage drops. I have had the Battery tested at an accessory shop = simple voltage check, but I intend to take it to a auto electrical shop for a proper check. I appreciate ll the feedback guys, I get very low when my car doesn't work properly. Still crossing fingers and everything else that the starter is fine.

[n4chv]

Been out again for a 15 mile run, and it's running like a Swiss watch. I'm starting to regain confidence and belief that it really is just very sensitive to voltage drops. I have had the battery tested at an accessory shop = simple voltage check, but I intend to take it to a auto electrical shop for a proper check. I appreciate ll the feedback guys, I get very low when my car doesn't work properly. Still crossing fingers and everything else that the starter is fine.

I'm really pleased to hear that your faith is gradually getting restored. The problem with these types of cars nowadays is that with all the electronics, the cars need to be used regularly and for longer journeys so that the Battery and all the systems get a decent dose of power so to speak.

A couple of dealers have suggested I invest in a trickle charger to help maintain the levels on the Battery but ultimately these cars just need to be used.

I own 3 cars and I do make sure that they all get used as it's a bit of a waste letting them sit on the drive doing nothing

Hopefully your auto-electrician will give the car a clean bill of health.

My LS430 has caused me a few headaches but thankfully it's all working fine and my faith and confidence is back

[plastic orange]

It seems that modern batteries give little or no warning about imminent failure. Mine was fine on Sunday, but failed on Monday and no amount of charging would have it hold it's charge. New Battery today and back to normal.

My motorcycle batteries have the same limited life too.

Pete

[mikeyv]

I have an Autocruise campervan based on a Peugeot Boxer, the handbook states 5 days as the maximum idle time.

Any more and it recommends disconnecting the damned Battery.

Twice now I've gone to start it after a week without running, only to be greeted with a load of messages (none of which is low Battery!!) and despite a fairly healthy cranking speed, it fails to start.

A quick charge, and all is well.

I wonder how the insurance would view the Battery being disconnected, with obvious security issues, should it get nicked?

Progress eh?