Russell Wheeler

12v Battery, or water ingress - its a 2008 RX400h (ie seive)

£276 for my 2006 RX400h with 1st Central

On 3/12/2024 at 11:07 AM, NEILJ said:

Hello Simon and JD

Thank you Simon for your in depth explanation of your cars problems.  Like you and your wife I love my car too or else I would not put up with this issue but it has got to the point now that I am looking at alternative vehicles on Autotrader and when I look the only cars I am drawn too are older Mercedes ML's , Toyota Rav 4's and possibly Mazda the rest I consider to be Junk after seeing the issues my neighbours have had with their BMW's and Land Rover/ Range Rovers .  There is Currently a low mileage RX300 on Autotrader that looks very nice but they too have terrible issues with water ingress so have resisted the temptation to go and look . My Rx like yours has no sunroof so the only place I can see where water is getting in can be the roof bar mountings which I have had off twice now and resealed so when the weather gets a bit better the bar in question is coming off again and I am going to try Tiger Seal this time, so will let the forum know if I succeed but as I have mentioned in a previous post the silicone sealant I used the last time kept the car dry for over eight months and I can only think that the expansion and contraction with the hot weather has broken the seal .  I am thinking that the Tiger seal has stronger bonding properties but will have to see.  I have had the car for ten years now and the problem only arose  after I had taken the car into the paint shop to have a rear bumper repair done after someone reversed into the back of the car , the previous years the car had always been watertight.  When I look through the forum it is like JD has said that there are a lot of Lexus cars with the same issue but when I spoke to Lexus service department, who by the way have always been very helpful  in the past,  to see if they could shed any light on the problem they said " it just does not happen on Lexus"  they have never come across this problem hmmmm perhaps they should read the forums like we do aye.  So Simon and JD thank you for your replies I will continue to investigate and let you know if I have success or failure in the coming months or if I give up and buy a nice old Mercedes ML320 petrol , definitely not a stinky diesel but this issue like for many is putting me off considering Lexus in future which is a shame as I have loved the mark especially my SC430 I cannot bear to part with that one it is one of if not the best car I have ever owned.

 

Neilj     

Never heard of leaks, like they have never heard of the small starter Battery causing a problem in a RX400h. Liars. They do leak especially as they get older, seals drying out, poor welds.

Water leaks on an 18 year old car. Not uncommon. Just needs time and patience to trace/seal them.

My 2006 RX400h  - looks like it needs a cambelt - the sticker says it was changed 2014. Any idea of costs.

Also it is on it's original Battery pack (seems to be working fine) - any idea how long it can last, and how much to change. Car has done 140k and runs fine.

I am concious of pouring lots of money into a 2006 car, although as a family we have owned it since 2009, it's going to need some serious maintenance this year. It's been 2 years since it's last service. Also I had a service plan with Lexus and the spark plugs are supposed to be changed every 60k. I can't find any evidence it was done at 120k. Apparently they are a pig to do.

On 11/13/2023 at 9:34 AM, NEILJ said:

I really can't fathom it

Morning All

Just thought I would post another update about this ongoing problem .  Since my last update we have had many downpours over this last month and the car has remained dry , no damp patch but since the weather has become colder the damp patch has returned this last couple of days.  I did buy one of those silica gel bag dehumidifiers that changes colour when saturated and have had to dry it out a few times this last week which indicates condensation.  To recap the windscreen has been taken out and resealed last January then I resealed the roof bar for a second time which appeared to resolve the problem for nearly eight months and now the damp patch has returned but has on many occasions remained dry after so many days of heavy rain the only thing that has changed recently is the temperature.  So could it be condensation on the windscreen and it is wicking onto the A pillar trim where it comes close to the windscreen glass.  I seem to remember reading something in one forum about replacing the pollen filter which I haven't replaced in a while so will replace that to see if that helps the cars interior to breathe better, yes I am clutching at straws but for £15 it is worth a try I reckon.  This whole problem only appeared after the car was hit on the back bumper and had to go into the body shop for repair and for the seven years I had owned the car previously it was never any problem and then as soon as I got the car back from the body shop the damp patch appeared after it rained or I washed the car.  I really don't know what to try next , any ideas anyone ?.

 

Neilj   

 

 

On 10/14/2023 at 12:02 PM, NEILJ said:

A further update , the leak has returned

Morning all.  Well after my last update I thought I had finished with this topic and it was all sorted .  It must have Been back in February/March that I had the roof rail off on the RHS and resealed it for a second time .  I thought I would leave it a couple of months before I reported on the success just to be sure so after many down pours and the car staying completely dry I reported in June that the resealing of the roof rail mount appeared to have resolved the problem.   

So we had a deluge of rain all night this last Thursday and Friday morning after the bin collection I was out taking the wheelie bins back around the back and as I walked past the car I glanced in only to notice a great big damp patch on the A pillar again .  I immediately got the car keys to have a closer look and hope that is was just a shadow or something but sure enough it was soaked again arrrrrgh  .....gger.  So what is happening is the car body flexing and breaking the seal , why should it come back after nearly eight months and many downpours without issue and what do I do next take it all off again and reseal.  The roof bar end cover clips are very fragile and I wonder if they will stand up to many more removals so after trawling through this forum I stumbled on a post where someone has recommended a product I have never heard of called Captain Tolley’s Creeping Crack Cure (leak/crack sealer). So wondered if anyone could comment or tell us if they have used the product successfully.  It is worth a try for £10 but just wondered if it might stain or affect the paintwork , any ones experience of using this product would be most helpful if they have the time to post thanks.

 

NeilJ

 

 

 

Yep, used it and it does seem to work - It's a liquid when you pour it and it creeps and then sets. Will only work on tiny cracks.

Mine is the same, and I do live by the seaside. 2020 was the 1st mention of corrosion underneath on mine.  Removed the spare wheel, cleaned and used hammerite on both subframes, then waxoyl all areas I could find. Seems to be keeping the worst of it at bay. Doing nothing means it will eventually rust away. The subframes should not rust out from the inside, if they have then it would have failed the MOT. The advisory must be for rust they can see (ie on the outside of the subframes). At 17/18 years old, you do need to expect they will be rusting underneath. Some older RX300 owners have had to have new subframes (or scrap the car)

Take out the boot liners and the back seats, see if the hybrid Battery is submerged

Check for water leaks, if water gets in to the hybrid system it causes all sorts of problems. There are lots of posts about leaks and how to cure

2 hours ago, NemesisUK said:

He should notice the lack of self-levelling and headlamp washers?

True - I knew about headlight washers  - which it may have as standard - Self leveling, my car has conventional springs and shocks.

On 1/29/2023 at 12:40 AM, not impressed said:

Your independent garage is risking it's MoT testing licence and your road legal status/insurance etc.. by ignoring this 'blindingly' obvious statement in the MoT tester's manual -

Existing halogen headlamp units on vehicles first used on or after 1 April 1986 must not be converted to be used with high intensity discharge (HID) or light emitting diode (LED) bulbs. If such a conversion has been done, you must fail the headlamp for light source and lamp not compatible.

This does not refer to complete replacement headlamp units which may be constructed with HID or LED light sources.

If a complete headlamp unit has been replaced with a unit that was manufactured with HID or LED light sources, it must not be failed for ‘Light source and lamp not compatible’ but it must meet all other requirements detailed in section 4 of this manual specific to the type fitted at the time of test.

 

You are correct, it should fail the MOT by converting to HID, however as the RX400h was also available with HID (Mine is) then the MOT inspector is not going to know.

15 hours ago, Lozsta said:

Hi Russell thanks for the advice but this review unfortunately counters the use quite well

 

"Don't waste your time and money on this junk. It might be fine for a leisure battery or something that does not move about but it is not sturdy enough for a car. The thing is poorly made, does not clamp over battery terminals securely without a shim. I removed mine after a couple of months as it was causing electrical issues with the car. Connection was not secure enough and components were not getting sufficient power."

I purchased an blank OBD port, and soldered the connections from the solar panel to the positive and negative points in the OBD, so the solar panel connects directly into this. Your Battery should not discharge overnight. Mine takes about a week - which is not ok for me - as sometimes the car does not get used from Month to Month. I have heard of a solution where a larger Battery is located in the boot  - however this requires significant changes to the wiring as you need to get the power from the boot to under the bonnet.

When it warms up I will go underneath and have a look.

I use one of these in the winter. It's not a very elegant solution but does work.   https://www.amazon.co.uk/Battery-Isolator-Switch-Power-Leakage/dp/B07J34S5DH/ref=asc_df_B07J34S5DH/?tag=googshopuk-21&linkCode=df0&hvadid=224431698442&hvpos=&hvnetw=g&hvrand=16332938530141334352&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1007098&hvtargid=pla-757317365237&psc=1&mcid=3f6a06c2dbf432e1a17c232a91df02e9

You can jump the 12v starter Battery from a 12v source. Just don't jump anyone elses car from yours. And like you I have looked for a larger capacity one, there isn't space under the bonnet - hence all the problems. I believe they fixed it in 2009 with the next generation by putting a normal sized Battery in - which is no help to anyone with an earlier 400h

Yep, it's a pain, mine is exactly the same. I use a solar panel in summer and a Battery disconnect in winter. I also carry a jump pack in the glove box, so have never been let down.

Another pass this year. Again another advisory for rust. I rubbed down and hammerited both subframes the other year, but the advisory is for general underbody corrosion. Anyone used lanoguard - my regime of hammerite and wayoil doens't seem to be working (or it's just the car getting older). On top it looks perfect, not a spot of rust.

I have the same problem, as the car is only used a few times a month. In the summer I have a solar panel that keeps it topped up. In winter I have a Battery disconnect, so pop the bonnet and lock the car - then disconnect the Battery. It's a pain but has been like that since I inherited the car. My Dad used it a few times weekly so the problem didn't occur for him.

On 1/19/2022 at 1:30 PM, Malc said:

Wot on earth could need this doing on such a newish car for heavens sake  ???

Malc

15 years old, the underside of these cars does not seem very well rustproofed. I have been out with a wire brush, hammerite and waxyoil with mine - and it was quite rusty - commented on the MOT

It is hidden under the cover sills, so weld plates on, then put the cover sill back on. You won't see it. Is the otherside similar ? - Might be worth rust proofing it (unless it's already too late)

I used a 55mm flexy pipe in the end, angle ground off the old exhaust then put this in the middle. Had to reduce one side a little by cutting down the edges a little, so it squashed down. Repair complete and working fine.

On 9/19/2023 at 6:33 PM, b4u2 said:

@Russell Wheeler

Have you had it since new for 17 years?

It's been in the family  since 2009 - my Dad purchased it at 3 years old with 90k on the Clock for 15K. Seems like a bargain now. I inherited it 3 years ago

Mine's 17 years old, never any problems. Always starts and runs. Yes MOT time can get expensive with worn rubber components - but it is 100% dependable

The Bluetooth is more annoying. I can't play music though it !

On 4/8/2022 at 11:13 AM, Brunel said:

Useful post thank you.   My 172K 2009  centre section is blowing.  I shall see if someone can do a repair cheaply as I'm think of selling it.

One question - what is the 'thing' sticking out of the side? - the holes are in fact where that meets the exhaust.

 

Regards

 

IKB

 

 

Yep, that's where mne has developed a hole - it just needs sleeving as the rest of the exhaust isn't bad