Dead Battery.

[Foulsbane]

I came out to my Lexus the other day to find that she wouldn't respond to my touch, had to resort to using my key. Battery totally flat !!

To cut my story short, transpires I hadn't locked the boot lid down, problem solved.

However, I am now looking at a mini charger / starter that feeds back to the car Battery via the cigarette lighter port. It's so small it can fit in the small glove compartment.

Has anyone tried this kind of thing ?

I can't find any English reviews worth listening to.

[Mybikes a cx500]

Most cigarette lighters are only connected to the Battery with the ignition on or at "accessory" Even then, you can only trickle charge a Battery.

So not very useful!

[steve2006]

If the car is used regularly and nothing is left turned on the Battery should maintain its full charge without further intervention.

There is a good range of the "Smart" chargers around now which can be left connected to the Battery but will automatically stop charging when the Battery is at it's optimum charge rate.

As mentioned by Mybikes the cigar lighter sockets are all powered via the acc supply and would need rewiring for a plug in charger.

[Bluesbreaker]

I've got a solar charger, I used it on my Boat,it measures roughly 300mm x 100mm, I could leave it up against the windscreen,connected to the Battery,and with any daylight,sunny or dull,it would keep the Battery fully charged, I dare say,you can buy them on eBay still,my one cost £20,-well spent.

Ron-I left a door,not quite closed properly once,on my LS,-it flattened the Battery overnight, it's easily done.

[Foulsbane]

I never had a hint of a problem until the other day, now I check that everything is 100% before I say goodnight.

LoL

[N55GUS]

I removed my boot bulbs when I first bought the car but I still have Battery problems when the car has been standing for a week or more, and I don't have a metal emergency key to access the 430.

I posted on here a while ago about my tales of woe, but my mechanic friend has come up with what I consider a good idea.

He has connected two wires to the Battery terminals and duct/electrical taped them to the bottom of the windscreen, so that if the Battery is completely flat and I cannot access the car then i just need to connect my charger to the two wires for a few minutes and I will have enough power to open the doors. Then the Battery can be charged safely and properly.

[PEPE]

I've got a solar charger, I used it on my Boat,it measures roughly 300mm x 100mm, I could leave it up against the windscreen,connected to the battery,and with any daylight,sunny or dull,it would keep the battery fully charged, I dare say,you can buy them on eBay still,my one cost £20,-well spent.

Ron-I left a door,not quite closed properly once,on my LS,-it flattened the battery overnight, it's easily done.

Iain, you are absolutely right. Three days ago I left a door of my Mk4 open overnight. Fortunately I remembered what you had said here and didn't attempt to start my car. I simply opened the bonnet and put a voltmeter across the Battery terminals. The reading? 3.55 volts!

[Foulsbane]

I followed your tip Iain and bought a Solar Charger for about £16 , folds up nicely. I bought it as a precaution for when I go on holiday later this year , the car will stand for 15 days. I suspect that may be long enough for the security system to run the Battery down, now I need not worry, I'll take some jump leads in case my relatives suffer a dead Battery.

[symon]

Hi Ron , do you have the smart key system switched on ? in the hand book it suggests if leaving the car for a couple of weeks to turn it it off , as the system is constantly looking for the key ! , and may drain the Battery ,

[Foulsbane]

Hi Symon,

It's always on, just love the keyless system.

But when I go on holiday I plan to switch it off and still use the Solar Charger as a safety backup.

[N55GUS]

I went to go out Saturday night and the remote keys wouldn't unlock the doors, if you remember I do not have a metal key. FWIW the 430 had only been standing 24 hours and had given no signs of a poor Battery, I went out in the Mrs Fiesta.

So Sunday morning and my friends handiwork came to the fore, I reached under the passenger side wiper blade and pulled out two wires which were protected by rubber casing.

I put my Battery charger on these for 5 minutes and there was enough power to open the doors, then I took off the negative Battery lead and charged in the normal manner.

I am perplexed by this dead Battery problem as the Battery has been tested and is only just over a year old, maybe after reading the posts I need to have it re-tested, would a more powerful replacement help?

Also I think the car was left with an electrician for a week when I was on my hols but they could find nothing wrong, would an ECU check be worthwhile? TIA

[steve2006]

You either have some undetected current drain or the Battery is faulty, warranty should still apply to Battery so I would return it to the retailer for testing/replacement.

[N55GUS]

I will probably go to the Lexus main dealers this week and have the Battery checked, if the Battery is not 100% then at least with a Lexus supplied re-placement I should be OK, unless it is a security/immobiliser fault that is causing the problem.

About 15 months ago the Battery was replaced by one which is now my current one, the old one was deemed faulty by Green Flag or whoever, but the re-placement was obtained and fitted by my mechanic.

On taking the original one back to the suppliers, they did all sorts of tests and it showed as not being faulty.

I think a BM previously posted that unless the Battery is 100% then problems will occur.

[DaKa]

I tried using exactly this to keep the baterry charged as my LS430 is seldom used. It had the opposite effect connected through the cigarette lighter as the Battery went flat quicker it seemed - e.g. The car must feel the lighter is on. I did find however that it worked if you connect the charger directly to the Battery (mine had an alternative crocodile clip connectors). However, this means leaving the car with a small wire out of the corner of the bonnet and into the passenger door. Okay for when left in a garage or long term carpark, but not practical to leave it connected while driving regularly.