Maduggo

There is a voltage regulator that is built into the alternator if the battery is charged up to its limit the voltage regulator should stop charging the battery and does this automatically,if it is not fuctioning properly and the battery is getting overcharged the curcuit relays should protect the system that is what they are there for. It looks like the curcuits that are vunerable to voltage spikes like the lights and the power steering are the first to go. If the engine is then stopped and started again the voltage that is used to start the car will take some time to build up again in the battery and if you are doing short journeys constantly the battery will not overcharge . I suggest you get both the alternator and battery checked. I have a thread of my own on this very issue, i have replied here as one comment stands out. if it is not fuctioning properly and the battery is getting overcharged the curcuit relays should protect the system that is what they are there for The last time mine did this i did not have the stereo on, i heard a click from the area of the console, where the gear selector is situated, i cannot guarentee this location though, i didn't hear any click when i touched the keys and all the dash lit back up again. Maybe we are getting close to solving this little enigma.

Your description of the fault appears to be identical to my issue, the problem happened today on my way home from work, i tried your wiggle the ignition key, like you say, everything came back to life as though nothing had happened. One thing i did notice is this, i was driving with no music on, when the dash went dead i heard a click come from i believe the console area with the gear select sits, i did not hear a click when the dash lit back up. With the bulb comment, the car has no blown bulbs in any location, all bulbs are the correct fitment as per handbook, the battery is a maintenance free job. Engine bay fuses all look to be in good condition, no crud or damage, i did pull them and reinsert in case of any poor connections on them. Voltages across battery 12.51v car at rest 14.20v just engine running, no lights heating etc 14.25v engine running, A/C on and set to 25*, lights on normal usage, front and rear demist on blowing at half the scale on the display I do not have any user guide for this car such as a haynes manual so i'm working blind so to speak. How would i check the alternator and where is it hidden away. Do any of you have such a manual i can get a copy of, i have seen those lexus jobs on ebay and the price is well expensive It's getting my curiosity up is this one, i don't like to lose to a car, no motorbike ever beat me so i'm not going to be beat by a car, even a lexus

Yes the engine remains running, i haven't tested to see if it runs any faster than my normal driving, when it happens all i have done is to safely pull over, just in case. Battery terminals were the first thing i checked after i read on here that it could be a battery issue. Engine earths, where are they all located? Will check the battery voltage with and without engine running tomorrow, also the fuses in the engine bay. Speaking of fuses, where are the compartment fuses located, i don't seem to be able to see any panel to remove to locate them.

Hiya folks Been a little while since i was here. Got myself a 97plate mk3 with 99k on the clock, less than a grand after knocking down the price when i spotted several issues not mentioned in the ad. Brakes warning light on, needed new discs all round as well, 2 tyres were close to the limit, boot seal was leaking, small spot of rot just inside wheel well. Was asking £1500 for it but bargained down to £900, and he filled it up and taxed it for 6months. All fixed up now, tyres £320, discs / pads £220, boot seal £90 from lexus grrr, sorted all the jobs myself except putting tyres on the rims, sorted the rust spot and repainted the area in and out. The one issue i have just noticed worries me. When driving along, the entire dash goes dead, the steering goes heavier but not like it is without power completely, no indicators or lights, no speedo or rev counter, happened 3 times in the last 2 weeks. Turn off the ignition and restart the car and all is normal as though nothing happened. New battery was fitted last year by Lexus. Any ideas ?

BUT....you DO get TRACTION CONTROL, which is an omission on Ser 3....and the Satnav ain't TOO bad really! Each new LS (up to 430?) was a distinct upgrade on the previous one. It does just depend on just how much you need. Certainly a 3 ser is fine. I switched to a Ser 4 for the Traction bit. Yes, my 430 brochure tempts me, but (as Simon says, how much do you want to spend for subtle upgrades?) Satnav i not worried about, they only good for the last 3 miles of the journey, planning and thinking you can beat a satnav. Does the traction control make a difference, i don't plan on launching myself about like a rocket, that's why i rode a bike to do the launching bit. As for money, i got a £4k slush fund to play with so anything up to that i can use, i don't plan on spending it all on a car though if i can avoid it. As i said before, good condition with history is my main criteria, mk 3 or 4 is of no real importance in that respect, extra bells and whistles is a bonus, but whatever i go for it must be original, i won't go for anything that has been modded, in the bike world it means a mess as the original parts are usually lost

Hiya mate I used the search and found this when i was hunting http://www.lexusownersclub.co.uk/forum/index.php?showtopic=73395 click the link above the car on the page hope it helps

Hiya Mileage doesn't bother me, iv'e just sold my motorbike with a genuine 102567 miles on her, and we all know bike engines suffer more than cars do, so i would easily believe a well looked after and serviced lexus could easily reach over double or triple that.

Hiya and thanks After i posted the message I found a buyers guide from a search, contained lots of useful info, I printed it out for reference. MPG is not a major issue, I just finished my motorbiking career and want a slice of luxury for a year or so, was told LS4** is the way to go for that apart from rolls royce of course. I have seen a few on Ebay and Auto trader that I like, Mk 3 and 4 don't really bother me as long as everything works as it should and the fluids are as they should be. Most of all I want service history with payments to suit. As for the other tips i have found by browsing im well impressed. Chris

Hiya folks. Newbie here. I want to pick your brains as to how to go about selecting a LS400, what to look for etc. Any advice is greatly accepted. Chris