Battery Failure

[crb]

New RX 400h bought november 2006 milage is at present 3500. went on holiday for three week when I returned the battery was flat, I had to jump start it from another battery, very difficult when you are on your own ? as soon as you start the car get out to disconnect the engine stops and swtches to the drive battery than the car battery goes flat again. the only way to move the car is to have somebody remove the jump leads and drive away.

I have returned the car to Lexus at Hedge End Hampshire and they have assured me there is nothing wrong, and have informed me by letter that "Lexus advise if storing the vehical for more than 10 days disconnect negitive terminal of the 12v battery, this prevents discharge due to current to ECU's. Also advised by Lexus for battery maintenance (including the hv Battery) charged every two weeks for 30 minutes by starting the hybrid system (Ready) with all electrical components off"

This of course means you can't park up for a two week holiday without disconnecting the battery, not something I fancy doing at 3am at an airport carpark in the rain.

Has anyone got a solution.

Hi

I had a similar problem and bought a solar trickle charge from Maplin leass than £15. At first I connected it via crocodile clips to the Battery terminal as the cigarette lighte works only on ACC. I then spoke to my Lexus dealer and asked them to wire it in so that I can connect it and place it on the dashboard whenever I want. The cost of the direct wiring was £120 ouch bnut better than having to deal with a flat Battery on a dark and wet night or for any other time for that matter.

[Dave Aberdeen]

I too have sufferred the dead Battery after an extended period of parking,

Lexus replaced the Battery stating the old one had ' dead cells' however after reading all the tales on this form and given that I do leave the car in the garage for extended periods I made up a timed trickle charger using an old timer from the gas central heating, a 12v relay and a trickle charger from Halfords

The charger is switched on for an hour each day I am away and since it is connected via a relay it completely disconnects itself after an hour ( that way there is no risk of the Battery discharging through the charger)

I fitted a rubber mounted two pin socket across the Battery and mounted it adjacent to the radiator at the front of the car

I have used it several times and have had no problems starting even after the car has been left for 30 days

[katabrontes]

Does anyone know if the problem of Battery drain applies to the RX 350 and RX 450. All the posts seem to for the earlier versions so maybe Lexus has resolved the problem on the newer versions.

I cannot believe that Lexus does not know the cause of this problem and their continuing denial and false reassurance certainly does them no credit. I am seriously reconsidering my decision to buy one and I suspect so will many others if they have read this series of posts.

[Duncan Roberts]

Does anyone know if the problem of battery drain applies to the RX 350 and RX 450. All the posts seem to for the earlier versions so maybe Lexus has resolved the problem on the newer versions.

I cannot believe that Lexus does not know the cause of this problem and their continuing denial and false reassurance certainly does them no credit. I am seriously reconsidering my decision to buy one and I suspect so will many others if they have read this series of posts.

You have clearly not researched the subject on here, threads galore - the petrol versions, RX300/350 are not involved and the issue is resolved on the RX450 so far as appears to be known here. This remains an issue on the RX400, the cause is known - no physical space for a larger Battery in the engine compartment. That cannot be cured, some people have used a different Bosch Battery as a palliative.

[katabrontes]

Not quite accurate Mr Roberts. You will see several posts relating to RX300s where the problem seems to be related either to the Auto headlights function or the alarms. While part of the problem with the RX400 is certainly the small capacity of the Battery using a larger one will only improve the available downtime quite modestly (from say 9-10 days to about 2 weeks which is still pretty marginal if you go away and park in an airport car park. It is pretty clear from the threads that the problem is not only the Battery capacity but the excessive standby drain caused by the various electronics in the car not being shut down when they are not needed. Hence my question remains pertinent and I would be interested in a more thoughtful and reasoned response.

[Duncan Roberts]

Not quite accurate Mr Roberts. You will see several posts relating to RX300s where the problem seems to be related either to the Auto headlights function or the alarms. While part of the problem with the RX400 is certainly the small capacity of the battery using a larger one will only improve the available downtime quite modestly (from say 9-10 days to about 2 weeks which is still pretty marginal if you go away and park in an airport car park. It is pretty clear from the threads that the problem is not only the battery capacity but the excessive standby drain caused by the various electronics in the car not being shut down when they are not needed. Hence my question remains pertinent and I would be interested in a more thoughtful and reasoned response.

NOT so, reasearch here would be invaluable. ANY car be it a Lexus or a Ford or anythiing else can have defective equipment which causes a drain on the Battery. Odd RXs have had this problem. However, the RX400 has its own unique problem - the auxilliary Battery is simply too small to stand over about two weeks. the two isseus should not be confused.

Your question wll be adequately answered by consideration of the inumerable threads on the subject going back five or more years and no more consideration of a response is needed. Lexus know of the problem, it cannot be cured in the limited space available.

[katabrontes]

I am sure there is some truth in what you say. I cannot, however, see the point of reviewing 5 years of forum posts into a problem that, it appears, only Lexus could solve by fairly radical recall of all the RX400s which have the problem. Since it clear from some posts that this is not universal it follows that those which are affected are defective and it falls to Lexus to resolve the fault. Unfortunately as it is not a safety issue they seem to have ducked this obligation. In the long term it may not be a good judgement.

However, my question was about he RX300 and RX350 and did not involve consideration fo the Battery capacity since I understand it is 75AH on these. Several posts have clearly stated that the problem has been found on some RX300s and various suggestions have been made (auto headlights, standby drain of satnav and alarm etc). There may have been faults on some of the RX300s affected, this is not clear from the posts. Lexus agents seem to have persistently failed either to identify faults (on either RX300 or 400) or to deny that there were any. It is a;so clear from several posts that there is a degree of confusion and mixed messages from agents and Lexus themselves about the safety of various solutions that have been proposed (booster batteries, different brands of Battery, solar chargers, blocking diodes etc). This is unhelpful to owners and reflects no credit on Lexus who seem to have signally failed to support their products.

The problem does not, yet, affect me and may never do so if I decide not to go ahead and buy a 350.

It would have been helpful if Mr Roberts had actually answered my question instead of fending it off with an unhelpful smokescreen which would have taken up more time than it was worth.

It was a simple question and I hope someone else will be able to give me the answer which should take only a few words.

[Duncan Roberts]

My response was not unhelpful merely not what you wanted. Having been a member here for several years I regret to say that the subject has been done to death but is resurrected by newcomers but no new outcomes are likely.

What good would a "only Lexus could solve by fairly radical recall of all the RX400s which have the problem" approach do? The cause is known - the Battery is physically too small which constrains its performance. There is no room for a larger one. The problems which occur on a few RX300/350s would occur whatever the size of the Battery - those are faults specific to individual cars. The RX400 has its Achilles heel but it remains a good car and one which is difficult to beat

[Beejay]

The fact that the 450h has a bigger Battery rather proves the point doesn't it?

[katabrontes]

Mr Roberts claims extensive knowledge which, unfortunately, he seems unwilling to share. I have read all the posts in this thread which cover about five years. A few are well researched and contain useful evidence others seek more information. Perhaps Mr Roberts could, more usefully to members, consolidate the present state of knowledge about Battery life in a "sticky" which would be very helpful. I suspect that the changes to the 450 go beyond simply a larger Battery. I have addressed this point and do not need to repeat the argument.

I feel rather like David Frost in having asked the same question several times and still not been given an answer. Perhaps I will be forgiven for repeating one last time. I do not have any interest in the problems of the RX400 which are historic and irrelevant to me since I would not contemplate buying a hybrid at the moment. The economic justification is too weak.

Does the RX350 have the same problem of excessive Battery drain found on some (? many) versions of the RX300?