I guess I'm confused? Why would he not just try the DSR ECU replacement only first to see if that fixes the problem? A while back I remember seeing some who just replaced the DSR ECU and not the Rack, same symptoms here. The replaced DSR ECU fixed the whole problem. It was the only thing that had gone bad.

 

I think it was pretty well determined that the problem is with the stroke sensor in the ARS assembly. It's somewhat rare for an ECU to fail, though it does happen. His Lexus tech recommended replacing both the ARS assembly and the ECU, I suspect as a means of making sure the problem is solved, which is often a typical solution for such matters.

 

It was me , I bought it immediately when I saw you posting about it. Why wait? Extremely difficult to find spare part and price was ... let say more than fine comparing to 19 000 euros Lexus is asking for it . Seller does do not deliver to Finland, but I'm using proxy service. Hopefully all works fine.

@bclexus You have been so kind and helpful, I really appreciate it. Thank you and thanks for all others helping here.

Yes, it could be possible. Let's get back to this when I have replaced the part.

Exactly like @bclexus explained above. All evidence so far indicates that issue is in stroke sensor. I am aware of two persons in UK and chat with one person here in Finland who who had same symptoms and they need to replace only rack. Of course replacing the stroke sensor would be best option, but it cannot be replaced as stroke sensor have never been delivered separately. It could be that the rack was thought to be unbreakable, but over 10 years of constant getting wet, freezing and salting the roads eventually causes the sensor to get some moisture and dust inside looking like this and this . Lexus mechanic diagnostic was to replace both, rack and ECU, but I still think that most likely the reason is the stroke sensor and thus need to replace the rack. If replacing the rack does not help then I will buy the DRS ECU also. Lexus was asking 4500 euros for it, you can get (hopefully) new one from Amayama 750 euros and most probably used one much less.

So, now I'm waiting to get a part to Finland and then we'll see what happens ​​​​​​​

 

It looks like the seal around that coil pack failed, miserably. How'd it get so full of grit though? Or is that salt crystals? It looks similar to a stepper motor in a way, so decently sensitive. I'd be interested to know what the other poster finds whenever you send him the old part.

 

@WhiteGS450 - You don't know how much that pleases me! It has made my day for sure! I am so glad it was you that bought the ARS.

Let us know when the ARS arrives safely by the proxy service from South Carolina to Finland.

I hope this is able to put your car back on the road in Finland for many more years.

If you need to replace the DSR ECU that shouldn't a problem.

Are you going to replace the ARS yourself or will you have your Lexus dealer's service department do it for you so they can perform the calibration?

Hoping all goes well!

 

This is another stroke sensor detached from another replaced rack. Does not look good either.

Let say this way that I'm also eager to buy the DRS ECU - just in case , with reasonable price. Used ECU should not be expensive. Already asked from same seller I bought the ARS. If anyone can spot the ECU somewhere, just let me know.

It is actually pretty easy to replace. I have seen instructions with pictures how to do that, but I will not do it myself. It needs to be calibrated anyway and Techstream needed for that, so I will let Toyota/Lexus mechanic to do the job. It should be 3-4 hours labor maximum.

 

Finding a PN 89182-30040 Dynamic Rear Steering ECU is a rare one for sure - much like the ARS assembly is. I truly hope you can get the ECU from the same seller you bought the ARS assembly from. I don't find the PN 89182-30040 ECU available anywhere except for new ones at $2-3k or higher.

Lexus has offered Dynamic Rear Steering on several models including the RX 500h but I suspect the DRS ECU part number is not the same as your ECU and likely wouldn't work with your car.

You might want to contact the eBay seller with the $1,900 ARS assembly to see if he might still have the 89182-30040 DRS ECU from the donor vehicle his ARS he's selling came from.

 

I still think it's the DRS ECU only IMO. If you do get the DRS ECU, I would try swapping that only 1st, and see what happens. That would be the easier path.

As I said before I have seen this problem a few times on different Lexus but did not really get into because I don't have that system. I think the DRS ECU is the break in communications with the sensors and other, and that is why it's coding so many different codes and lights. I guess we will see soon, if you report back the results. Good luck!

 

I checked with Anderson Auto Parts 864 and the control module ECU in the car was 89182-30030 (112900-8502). The rear steering unit / ARS I purchased is the same as in my car 45900-30070. I also doubled check the VIN codes before my purchase and those matched. So steering unit should fit for sure. However, the control module 89182-30030 does not fit to my car, based on VIN. It needs to be 89182-30040 (112900-8512). Some kind of version difference. Maybe related to the fact the car is 3.5L V6 2GR-FSE ENGINE (same as I have) but 8-SPEED AUTOMATIC TRANSMISSION, where my car has CVT .. I guess.

 

How much do they want for the ECU that was in the donor car with the ARS you purchased? Maybe either (your OE or donor) ECU will be okay. The difference could be just something insignificantly minor (connector brand, gasket/sealant, etc.) that doesn't affect its useability or purpose.

 

For a price of only US $134.00, I would have just gotten this 1st and installed and then reset to test. It shows it was returnable also.
https://www.ebay.com/itm/38771547552...Bk9SR8aO-Pz5ZA

I switched AVS Strut ECU's with a different Module and was plug and play no problem. If those steering control modules were plug and play switchable would be a good test to see if on reset the lights clear and the least expensive cheapest route. That listing on ebay shows it's returnable if you need to. Hopefully the Rack was returnable also just in case. When trying to fix something like that it's always a good idea to just make one change at a time so you know what the fix was, instead of replacing 2 or 3 or more things at the same time especially with used parts to try repairing. Say it's the ECU only, you install both the rack and ECU at the same time, and the used Rack is bad, where yours was not. It's going to still code and unbeknown to you the used rack was bad you swapped only.

 

I think you are a bit confused.

I think that link is for the eBay seller's advertisement for a typical power steering ECU, not for the Dynamic Rear Steering ECU from the donor car that had the ARS assembly.

 

Maybe because I clicked that link for the link he posted in post # 39.

 

For the ECU, I don't really think it is the problem, my suggestion is to install the ARS unit first and see if you need an ECU or not.
Unless you get a really cheap ECU like less than 300$ then don't miss the deal, otherwise the cheapest option is to install the ARS and see what happens afterwards.

 

Agree. I think replacing the ARS assembly is all that will be needed except for the recalibration process. Hoping so because all the DRS ECUs I can find are new and very $$$.