Hayne

This is a great post Adrian and will hopefully be useful to us all when the time eventually comes. Hoe did you check the battery module voltages? Was this with diagnostic tool or just with a volt meter? Also, were there any symptoms before failure? And, how much did the guy charge you to repair it? Thanks. Giles.

I have found the receipt for the Hybrid Pump bearings. Not sure if the part numbers would make sense, so I have measured the bearings with vernier callipers so the correct parts can be ordered. I bought mine from Brammer UK Ltd, in Hereford (01432 276630). The part numbers are 61900-2Z and 608-2Z. They were in stock at the time. The dimensions for the front bearing are 22mm OD, 10mm ID, 6mm width. The dimensions for the rear bearing are 22mm OD, 8mm ID, 7mm width. Giles.

Sorry to hear that Mark. Well, worst case, a used engine will be about £2-3k and probably a couple of days to fit it. But, before you panic, its worth getting it properly diagnosed by a decent mechanic (not a Lexus dealer 'technician' !!!) Usually, if a cam belt/chain snaps, the heads need removing and new valves and cams need fitting. I don't know about the GS450h, but I imagine it would be a similar process. It just needs someone to work out what has been damaged and replace the damaged parts. A new engine? In my opinion; unlikely. Its also worth doing your own research. There is probably someone else who has had the same problem who has shared the solution on the web. I hope the diagnosis is not too serious for you. Giles.

You're welcome Komain. I will dig out the receipt this weekend. The bearings are a standard size that most bearing manufacturers will be able to supply, so I will post the dimensions on here too (if I can find my verniers!). Good luck with repairing your spare pump. If you need any help, just PM me your number and we can have a chat. Cheers.

Mark, I spent months looking for a used broken pump, nut it appears they are just discarded. If it does fail, it only takes an hour or so to replace the bearings. The best preparation would be to buy the bearings ready for if it does fail. I will have a look for the receipt from the bearing place for part numbers and dimensions. Giles.

Yes, hardly environmentally friendly. The scrappage scheme was a ridiculous idea. And now, the government want to phase out diesels by 2030 and Boris wants to start banning diesels from London. I have read that by 2020, plans are for diesels to have an extra £10 surcharge added to the congestion charge making it £20 per day if you have a diesel. So they make it attractive for us to buy diesels and now we have a majority of them on our roads, they want us to get rid of them. Of course, this is excellent news for Lexus UK !!! Hybrids will be a majority very soon, me thinks.

Hi Pete, The car just ground to a halt one day and showed the Hybrid System Fault message. I immediately restarted it and it ran fine in petrol only mode. I ran it for 6 months like this until I diagnosed the problem. Lexus never saw the car; I would never let them near any car of mine as they seen to have a history of replacing parts for the sake of it instead of properly diagnosing. I didn't take it to a garage (I never take a car to a garage unless I know what the fault is likely to be), only when I hired the ramp for the day. I read the fault code P2797 and did some research and saw that many other people have encountered the same problem with the same end result; a new pump! I then checked the power to the pump controller and resistance of the pump motor windings and fuse, etc. I paid a small fee to JustAnswer to get some advice from a Lexus Tech and he gave me the same advise; new pump required. I spoke to Lexus dealer and told them my issue and they too said that the only solution was anew pump at £3240. So, it is at that point I decided to investigate the pump fault myself, with the solution found and fixed on the same day. If you look at the post "GS450h Loss Of Power", that gives you all the details throughout my diagnosis. Giles.

Hi Mark, No, the pump on your link is a different part. From memory, it looks like a RX400h/450h pump. I have attached some photos. The pump can be seen from underneath the car when on a ramp. It is located on the lower off-side of the gearbox, so is pretty easy to get to. I had to remove the gearbox mounted exhaust bracket to get to it properly before removal. As you can see, it is a well engineered, simple part with one moving part; the impeller shaft. The three coils are fixed, therefore there are no brushes to wear out and the shaft has the magnets mounted on it. There really is not much to go wrong with it. It's just a shame that Lexus made a poor choice of bearing specification. The two bearings can be seen in the photos. One is located under the circuit board (this is the shaft position sensor board) and the other is at the bottom of the motor housing (can also be seen mounted on the end of the shaft in he photo. Hope it makes sense. Giles.

Hi Marok, I borrowed a ramp for a day and drained the ATF out of the gearbox and removed the Hybrid pump (four bolts) and wiring loom to the pump controller. I removed the pump impeller housing screws (3 screws) and found that the shaft was seized and wouldn't budge. So I took the motor housing off (another 3 screws) and found that the front bearing was seized, preventing the motor shaft from turning. It is a very clever and simple well engineered design, the pump and motor are in excellent condition, it was just the bearing that had failed. I took the bearing to a bearing supplier and they had one in stock for £7. They said this is a common size bearing readily available. I also bought the rear shaft bearing at the same time and re-assembled it, filled the gearbox up with new ATF, cleared the P2797 code and the car has now run perfect for the last 3 months, without problems. Someone else on this forum read my post and did the same on his LS600h and he now has a working pump again too. He also has two friends with the same problem and I believe they have repaired theirs too. A relatively simple and cheap repair, saving thousands of pounds. Lexus quote 9 hours to replace the pump. I took 7 hours, including investigating the problem and driving to the bearing shop. Just shows, they even charge you too many hours for a job that should take them no more than 4 or 5 hours to do when replacing a new pump. This is the fault that every GS450h and LS600h owner dreads. EVERYONE SPREAD THE WORD THAT THIS IS AN EASY FIX AND DON'T GO TO A LEXUS DEALER WITH THIS PROBLEM AS YOU WILL BE RIPPED OFF !!! Otherwise, you will be throwing away a perfectly good pump for the sake of a cheap bearing. I bought £50 worth of genuine ATF, 2x bearings at £14 and a ramp charge of £100. If a garage was to do this for you, it should cost around £500 parts and labour. Giles.

Exactly what I was thinking. I doubt there is anything wrong with your old callipers, as they are just seized up. A quick strip down and grease to lube them up and I expect they would be a good as new. I have done this on several cars now and it has always worked. A new seal kit would probably be only about £20 if they ever leaked. Yet another Lexus rip off. Main dealers are fine when a fault is covered under warranty, but at any other time, I would steer clear of them. In my opinion (and experience) they frighten people in to spending lots of money when they don't need to. Main dealers won't repair anything; they are either incapable, or are only allowed to sell new parts. Sorry to rant. I shall calm down now, but after diagnosis, they wanted to sell me a hybrid pump for £3240, when after my own investigation. all that was wrong with it was a £7 bearing!!

Thanks Bruce. I glad I could be of help. These days, no one seems to want to repair anything. Nowadays, everything is disposable and people just throw it away when an item breaks. The same applies to car components. Where has the old fashioned way of repairing things gone? Main dealers are different though. They have access to a huge amount of data about the vehicles they sell and access to manufacturers data which consumers will never see and data about wear and tear, service info, long term testing info and areas of common failure. Lexus DO know about the problem with the Auxiliary Hybrid pump, in fact, they have revised it three times since the first design in 2006. They will have cars permanently on bench test with hundreds of thousands of miles on them testing for failures. So why do they miss-diagnose problems so often? Are they forbidden not to repair any broken part and only supply new, highly-inflated cost parts to rip off the customer? Or is it shear incompetence? If everyone uses the forums to post their findings, we can all help each other combat the rip off culture of main dealers. It is great to have helped you out and I hope many others with GS450h and LS600h cars will find the info useful to repair their pumps as they continue to fail. I hope you have many more years of pleasure in your VERY nice car. Giles.

I'm 40 (bought mine at 38). I've had all sorts of cars, mostly in the luxury/executive sector. At 27 I bought a Jag XJ-S !! I just buy what I fancy at the time, but I've never been into hot hatches or small cars. My choice of cars hasn't really changed with age.

The Hybrid pump will eventually fail, typically between 120k and 180k on both GS450h and LS600h cars. But, it is not actually the pump that fails, it's just the two ball bearings within the pump which fail, preventing the shaft from turning. These bearings are about £7 each and are readily available from most bearing suppliers. The only down side is that it takes about 6 hours labour to change them, but it is a straight forward repair, so anyone with ramp can do it. See my post "GS450h loss of power" for more detail. Any local garage should be capable of doing this using my instructions, but unfortunately, Lexus don't repair vehicles properly, they only replace faulty parts, so avoid at all costs as you will be in for a £4-5k bill instead of a £500 bill !! My point being; don't let the pump put you off. These are wonderful cars. Incidentally, mine has 162k on the clock now and still drives like new. Save yourself £3k and go for the higher mileage car; after all, it is still low mileage!!.

So sorry to hear that. If you want to sell it, put it on eBay as an auction. You will get much more than £115 for it. Make a good advert with everything about the car and its condition and service history, etc, and 12 good photos and briefly explain the fault. Start it a £1 with no reserve and I think you will find it will sell for a good sum of money (certainly more than you have been offered). I did this a couple of years ago with my wife's MOT failure, 15 year old, BMW 3 series and I got £400 for it. There was a lot more wrong with it than your car and it was in poor condition. Well worth looking at eBay. Someone somewhere will have access to this part and will be willing to spend time repairing it, so it still has some value. See what similar GS300s have sold for which are spares or repairs. Giles.

Hi Les, Yes, the gearboxes are all CVT, but have an overdrive gear which changes ratio at about 60mph (the function that the failing pump controls). So its a CVT with a 2 speed auto. You are correct; if the pump fails, then the car runs in petrol only mode, but with some limitations. On hill starts, the car will be very slow to accelerate, as there is no electric power. The car will not go above 80mph as it is at the top of its variable ratio, without the overdrive gear. MPG is reduced by approximately 20%. Some people have experienced the car limiting its speed, by gradually reducing the limit (my car never experienced this). Overall, its good enough to get you home and to garage to repair the pump bearings. I actually drove for about 5000 miles with a faulty pump. A horse might sound like a good idea, but the cost of my wife's horses confirms that cars are definately the cheaper option!!! Giles.

Les, The pump is a very simple, well engineered part which will last the lifetime of the car, as there is only one moving part. However, the shaft bearings wear out over time and will continue to wear until failure where the bearings break down stopping the motor from turning. So, every GS450h and LS600h of this era will have this fault eventually. I wouldn't worry about this part, as it is a cheap easy fix. A garage should be able to change this pump when instructed how to do it. It took me a whole day and a ramp including investigation time, so a garage should be able to do this in about 5 hours, plus £50 for the ATF and £14 for the bearings. So, it is probably a £300-400 fix. The rest of the car is pretty reliable, but the inverters can fail and the hybrid batteries. The batteries can be changed individually and there are breakers who sell individual cell packs, so a failed cell looks easy enough to change, but I haven't experienced that yet (I'm looking forward to posting a solution to that when I get a failure). They are fantastic cars and are great to drive being very high performance. But, clearly, they don't exhibit the reliability of the non-hybrid models. I hope that helps. Giles.

Hi Komain, If the wiring has been checked, then there is likely to be something else wrong with the pump. It is such a simple design, that the most likely failure point (in my opinion, as I have stripped the pump down fully and inspected this) will be the front bearing. Before you look at this, have you checked electrical continuity of the pump windings from the loom connector? The pump has three coiled windings (like a stepper motor), so each of these must be measured. They are fixed coils and is a brushless design (i.e. no moving electrical parts). Remove the large connector from the Oil Pump Controller (mounted on the left hand side wheel arch under the air box pipe). Get an Ohm-meter, and measure each of the three power wires on this connector, in turn, to ground (battery 0V); i.e. hold the black probe to battery 0V and the red probe to each wire in turn. Each winding will be about 0.5 ohms. It only takes a few minutes to check this, so its well worth while (I wouldn't trust any one else to do it, even if they are supposed to be Lexus experts). If this is the case, then the pump is mostly likely to be electrically ok. Remove the pump and replace the bearings. I have a basic list of instructions further up this thread. It is not a difficult job to do either, you just need a ramp for a day. I will find the part numbers of the bearings and post them on here so you can buy them in advance. You will also need 5 litres of Toyota ATF-WS to refill the transmission afterwards. Good luck with the repair. Giles.

Thanks Brian. I hope everyone with a GS450h and LS600h can be rest assured that there is a relatively simple low cost fix. Giles.

This is normal operation. Throttle position does not directly relate to engine speed, like normal cars. Only a small rise in revs is noticeable. During an MOT, the emissions are NOT tested as it is a Hybrid. This is exempt as the tester cannot override the system to petrol only.

Well done. Glad you have resolved all your issues. It's a great feeling when perseverance finally pays off!

There are a number of independent key specialists around who can do this for you at a fraction of the cost. I have been told that the cheapest option is to buy a used key from eBay and they will code it to the car. My friend recently did this to his Peugeot and the guy charged him £75 to code it, saving himself about £200. I don't know if this guy can do it remotely, but he is in Malvern, Worcestershire and is called Elite Shoe Repairs. He has a lot of diagnostic kit which plugs into most vehicles. Maybe worth a try.

Colin, I never knew that disconnecting the battery would clear the codes! I always thought they were stored on non-volatile memory and had to be cleared by a reader. I stand corrected. Giles.

I'm sorry you're having so many problems. As an engineer myself, like you, there is no giving up and I'm sure you will get to the bottom of it. Regarding the code reader, I have never heard of this being illegal !! I have used code readers for years and have never heard of this. Even Halfords sell a basic code reader and I'm sure they would want to comply with the law, so personally, I would ignore this, buy yourself a code reader and repair your car. I'm sure there are many garages out there who are less competent than yourself with code readers!! I bought one of these ELM327 interfaces (similar to eBay item number 331206015268) and purchased the OBD software called 'Torque' from Android Play store for about £3. This is a great piece of diagnostic kit; well worth the small cost and will resolve most of your code reading requirements. This kit will read and clear your codes. I hope that helps. Giles.

Hi Stanley, It is unlikely that the codes will clear by disconnecting the battery, but a fault code reader will do that. You can buy a cheap OBD2 code reader off ebay. I bought one for about £20 that connects to my Android phone over bluetooth. Very handy to keep in the car instead of relying on garages to read codes for you. Incidentally, why did you need to change you stub axle? Giles.