2006 Rx400h - Inverter Leaking Coolant.

[RX400h]

From what I understand, our hybrid-related hardware and software is very similar to that of the Prius and as we all know, they are extremely reliable, even with 150,000+ miles on them.

The other thing to consider is the ultra-poor reliability of many German vehicles. You could certainly be far worse off by jumping ship to a German diesel-powered vehicle.

[lemon]

!!!=*&%$#!!!! I can't believe this. Had the timing belt changed today and when I got home, I had a good look under the hood to check for missing fasteners, cables, wires etc. Also torqued the passenger front wheel to spec (76 ft-lb) since the monkey at the dealership had torqued them on to near failure (obviously likes the sound of an air ratchet..zzzt..zzzt...zzzt..I guess those lugnuts are tight enough..oh what the heck..zzzzzt...zzzzt.

Anyway, while poking around I thought I'd check the inverter since I've been worried about a failure ever since the first one failed. Lo and behold, I have coolant leaking EXACTLY where the post above shows. That could be a picture of my leak, I kid you not. My leak is just not as bad as that one, in the sense that the pink crusty stuff is not as much as in the pictures above.

146000KM on this 2006 RX. Is this what we have to look forward to as these things age? Failing hybrid components? Are we beta testers for Lexus? Anyway, I'll be taking it to my dealership and see what they say. I'm hoping it's covered under the hybrid warranty as the motor generators are somewhere in there.

Really, really beginning to wonder why I ever traded in my Outback. It had 150000KM TROUBLE FREE!!

[katzjamr]

so glad it failed under the warranty period, at least. i am watching mine closely, no leaks.

[lemon]

Well, the original inverter leak that I had last year was covered under the hybrid warranty. I won't know until the dealer see this new leak and I argue with them and Lexus Canada as to whether this is covered under the hybrid warranty. Technically, if the other person that posted is right about it being the transaxle, it might not be, but my argument is that MG1 and MG2 are in there and it's leaking coolant from the inverter cooling system (which is separate from the engine cooling system), therefore, it must be hybrid related, no?

[Itr448]

Hi Lemon I am a fellow 06 hybrid owner and I came across your post because I also have the same leaking issue with my inverter. I discovered my leak when I was doing my oil change. I wanted to ask your opinion, as I have taken the vehicle to Lexus today to get it checked out. As a result, the service advisor told me that the lexus technician called Lexus engineering and the engineer stated to 1- fix the existing inverter module recall 2- then clean the pink cooling fluid and come back to the dealership in 5k for re-evaluation of the leak. I wanted your feedback on your experience with this issue. I didn't want the leak to get worse and damage more of the hybrid components. Any advise will help thank you.

[lemon]

Is yours leaking in the same spot as my pictures in this thread, or in the spot that are in the pictures that someone else posted? My pics are the inverter leaking, the other pics that someone posted are of the transaxle leaking. I have had both leaks on my vehicle.

I don't see the point to do the inverter recall (which is a circuit board replacement I believe) and then have to replace the whole inverter. Unless, the recall is an ENTIRE inverter replacement, in which case it still doesn't make sense - why not just give you a whole new inverter now? I'm still leaning to the recall being just the circuit board replacment, though.

It's kind of ridiculous actually - if there is coolant residue there, then the inverter leaked. Leaks do not mysteriously self repair. They should just replace it. If you are close to any sort of warranty that covers the inverter ending, then make sure there is proper documentation, so if you bring it back after the warranty expires, you can prove that the problem existed within warranty and Lexus was just too stupid to fix it at the time.

Let me know if it's the inverter or the transaxle for sure. Inverter is covered under hybrid warranty, transaxle is covered under powertrain warranty and they both have different expiry times/mileages.

[Itr448]

Thank you for the insight Lemon. I appreciate it. I'm picking up the car tonight with the recalls repaired (balancer and inverter module). Yes it is the exact same leak you experienced from the inverter itself. I haven't checked or researched the transaxle issue yet but I'll look into it tonight and hopefully no issues. Did you posts pics and description of where to look for the leak ? I was disappointed when the service advisor didn't know much about the internal inverter components itself. I asked if the leak is from the inverter box itself or was the inverter an internal closed system that has tubes inside that might be leaking. He stated he didn't know and that he had to go with what Lexus engineering said for him to do-- clean the pink leakage up, repair the inverter module, and tell the customer to come back in 5k for inspection of the inverter. I'm with you. If I know there is a leak, there's a leak. Maybe they are putting a bandaid on the issue now but I'll keep an eye on it until then. Thanks !

[lemon]

There are two sets of pics in this thread. The first post shows the pics of my leaking inverter. Later in the thread, someone added pics of their leak, which was from the transaxle (and I also had this leak). I would encourage everyone to check both these areas for leaks - the transaxle one is particularly hard to find - to make it easier, use a flashlight and look carefully at the pics posted in this thread so you are looking in the correct spot.

Again, the Lexus technician is a fool - if there is coolant residue there (pink and crusty) it has leaked, and the inverter should be replaced. I don't know why they wasted time/money/effort to replace the circuit board if you will eventually need a new inverter. I don't know of any leaks that self repair. In my case, they looked at it, said it had leaked and ordered a replacement (with the transaxle leak, they cleaned it off and asked me to return if I saw more pink residue in the future).

[lenore]

If it leaks, why cant it be repaired....unless the casing is cracked why wouldnt a new gasket, or gasket maker work...Is the sealing supposed to be so difficult that it cant be done in the shop....Seems very strange to me....

[lemon]

The whole inverter would have to come out to seal that area. I'm also thinking that coolant leaking out at that point, would likely also involve coolant leaking internally. I don't think a new gasket with liquid damaged internals would be a long term solution. But that's only a guess - I'm not quite sure how the coolant flows through the inverter, though I can check my service manual. It's probably similar to the MGR (electric rear differential) - the service manual is quite specific - No User Servicable Parts Inside.

In my case they looked at it, confirmed it was covered under hybrid warranty (I think they also approved it with Lexus Canada), ordered me a new one and about three weeks later the part arrived and they replaced it.

[jdogg333]

Had my mechanic do oil change and he noticed some coolant leak. I took the RX to dealership to do IPM recall and told them to check for leaks around the inverter. Service advisor said that there was "seepage" and this is normal. <How can a leak be normal???> Im at 65k and would hate for something to happen when warranty is up.

Heres what is on my invoice... "Customer States: Independent shop stated car has a fluid leak-check and advise." Correction-"Normal seepage from intverter per Lexus"

IMO seepage=leak and need to be fixed. I will contact Lexus Corp and see what they say.

[lemon]

I'd contact Lexus head office and/or get another dealer to look at it. I've never heard of normal seepage either.

[rleec]

Hi,

I'm a long time member but a new poster. I'm hoping that one of you experts might be able to provide some advice. I found a coolant leak today on my 2006 RX 400h and I'm not sure what the source is. I've attached a couple pictures in the hopes that someone might be ID the source. This is likely something that I'll have fixed at a dealer but want to be somewhat informed before taking it in.

Thanks in advance for helping out a mechanically challenged owner...

Rick

[maseace]

See if you can find where it's leaking down from - maybe from higher up. It could be as simple as a loose hose clamp or a small hole in a hose. Also there are two separate coolant systems - engine and inverter.

[ZeusG]

my 2006 400h with 87,000 miles developed exactly the same transaxle leak! My pictures would look identical to the pictures above. I have inspected the inverter, which was already replaced under the recall before and I do not see any leaks from it. There is a black plastic cover on the transaxle and I was able to unscrew and shift it aside to see where is the source of the leak. It seems like it is coming from a joint where two metal parts meet. Everything above it is clean and dry. Does any one had an experience fixing this leak? The leak appears to be intermittent and very slow. I add about 2 oz of antifreeze every 3-4 month to the hybrid coolant reservoir .