Hi all,

My new to me '01 LS430 has a few things that I'm trying to sort out including:
Intermittent missing when idling warm, expecially in reverse gear
Sluggish
what sounds like pinging noises from time to time
VSC off, sometime abs too.
The OBD port won't communicate with readers - fuses are fine, wiring looks fine, various readers power up but that is as far as they go.

Anyway, I wan't to rule out the ECU as the cause of some of these issues and get obd communication working to help narrow down the problems

to top it off the ECU model in mine is 89661-50600. I can't find the same one anywhere on the internet. The local ECU repair chain has never seen one and says they need all sorts of things to bench test them at a price and timeframe which is not-going-to-happen from me.

So my questions:
- Is there a list of the different ECU numbers used in 00-02 LS430's?
- Will an ECU from another model of LS430's of a similar era (ie 5 speed smart key) run in my car ok? - ie buy a 550, 551,552, 660, 680 > install > code keys 30 minutes and run the car?

Cheers

 

Hi, I have a later model 2004 LS430 so it may be different but hopefully i can give you some advice as I also replaced my ecu in an attempt to fault find/fix a transmission fault. It didnt fix my fault but i successfully changed the ecu myself without issue. The same prinicples may apply to yours.

First of all i would only get another ecu with the exact same part number. I got mine from a wreckers online. Look on ebay or google and see if there is anyone selling out Ls parts from a wrecked car the same model as yours and see if they have the ecu. Thats how i got mine. It was $400 second hand. On my model LS there was no need to recode any keys etc.

From my understanding if you are only replacing the ENGINE ecu within the engine bay then no key recoding is required.

​​​​​If you are replacing one within the cabin then yes it needs key recoding. I was only doing the engine bay ecu so mine was a straight swap - plug in, but I still needed to callibrate the new ecu once installed otherwise the security system kicks in and the engine will turn over but not start. That happened to me, but it was no big deal, i just recalibrated the new engine ecu by performing a calibration via the obd port under the drivers footwell. You connect a few certain points in the obd port plug (google it) then leave the ignition turned to "on" position with the keys for a certain time (about 5 to 10 mins i think from memory) then the car recognised the new ecu that was plugged in and the engine started. I am still using my swapped over engine ecu with no problems, I was just sad it didnt fix the transmission quirk.
This was my experience, hopefully it will be the same process for your LS.

 

Cheers,

I would do exactly that except I can't seem to find my model of ecu anywhere - it's 89661-50600. Nothing on the various country ebay sites or lexus part sites. None on gumtree. None at the local wreckers The only mention I could find on Bing or google was to some sites in russia offering immobiliser removal.

Maybe it'll be a case of playing the waiting game until one finally surfaces. or taking a gamble with one of the plentiful units to find out what happens.

Good news in the meantime however - finally established some form of communication with the ecu using an OBD link MX bluetooth adapter and an android tool called car scanner pro using the iso. I also went through the engine bay and plugged and unplugged all the electrical connectors that I could see so not entirely sure if that had something to do with the communication working or if it was coincidental, though none of my other apps will connect with the car using the same adaptor.

Codes that I saw were: c1400, p0110, p1354. It confirms the car is running in open loop which would explain the sluggishness. Definitely something awry with the o2 sensor responses too.

I've ordered a TIS cable given communication by the OBD2 port is now working. Hopefully this will shed some more light on what is causing the LS to run so roughly. Hopefully won't need to get another ecu.

 

No worries, hope it works out. I have had a look and from what i can see the good news is that engine ecu's for the LS430 in Australia from late 2000 up to 2003 (in 2003 only the ones with the 5sp trans) are the same part number 89661-50600 so one from say a 2002 should share the same part number as your 2001. I googled and can see a few 2002's being wrecked in Australia at the moment. Perhaps contact one of those and get them to double check the engine ecu from the car. As long as its the same part number it will be fine. When i did my engine ecu swap mine is an 04 and i used an engine ecu from an 05 with no problems.

 

I've got a 2000 LS430 that also has a few issues. If I can find the part number on my ECU I'll post it up for you. This pinging noise you hear, does it happen when you come off the throttle and pick it back up again? Also at varying volumes, and coming from the left front footwell area? Might pay to check in New Zealand as well. Try Trade Me, and also try Toyotas Galore in Auckland, they may have an ECU for you in stock

 

List of ECU part numbers at https://lexus-usa.epc-data.com/ls430...ic/8404/89661/, you may need to go back a few steps to select a body code matching your geography (e.g. General, Europe, Japan, USA/Canada, GCC), or entering your VIN should also get you to the correct catalogue.

There is a thread on these forums describing engine problems that were difficult to troubleshoot, and the problem ended up being the engine coolant temperature sensor 89422-30030 (corresponding gasket 90430-12005). Consider changing this part out while you're in there, cheap and easy enough.

There is another thread on here about strange transmission issues, and the problem ended up being the 2 transmission speed sensors - taking them out and cleaning them solved the problem, also easy enough to do.

 

Where are those two speed sensors located?

 

I had to Google to find it again. See https://www.clublexus.com/forums/ls-...s430-base.html

 

Thanks for the replies. Good to know you found some wrecking cars - I was looking just for the ecu number - should have googled wrecking :-) next time.

So the good news is communication is working with my original ECU now. And my VCI cable arrived. Can see and change sooo much more than the elm adaptor.
(A little tip for anyone trying to get the VCI driver to work on windows 64 bit, The driver itself is the same as the 32 bit version but for some reason, the supplied installer doesn't run properly. The work around is extract the files from the installer, copy most of the files to a folder in programs files and about 10 manually added entries in the registry, reboot, tell tsi to use the manually added adapter. Took about 10 minutes to install correctly after several failed attempts with the wrongly supplied instructions first. Happy to make a how to if interested)

The codes causing the rough running in my case were the VVT solenoids. I have a feeling these were triggering the VSC off as well. So I reset the codes and had to perform a yaw sensor refresh last Friday. It was then running great that evening.

Until Saturday morning, and vsc lights back on, but not the vvt codes. So I changed the oil/filter as the oil was on the low side of the stick, reset the yaw sensor again, gave it a full tank of 95 octane.
It has been driving perfectly ever since and no pinging, no surging and no engine codes. Just creamy smooth power. Going to run it for a while longer to see if the vvt solenoids actually need replacing or not but so far good.

 

Hi Aus430, just wondering how you got the comms working? What there a wiring issue you found or something? Very curious to know as I've lost comms too from my ECU to Techstream (Techstream was working and still works on other cars) a few days ago. My ELM327 unit doesn't communicate now either. Power and grounds are there on the connector. The serial waveform doesn't seem to be there.

BTW - I'm in Oz too with a 01 LS430 that I've had a for a few weeks.

 

Hey Macro,

I don't really know what exactly made it talk in the end.

The steps I took were:

I pulled the computer out (power disconnected obviously), had a look at it, decided the caps were fine and then plugged it back in.
I then went through every single fuse in all of the fuse boxes (6 from memory and a lot of fuses in the car), replaced the cigarette lighter fuse which was blown.
I then proceeded to go through several apps on the phone until I found one that would speak the right language to the computer - car scanner. I couldn't and still can't get other apps such as torque, obdlink,etc to work on the LS430.

My Techstream cable didn't turn up until after I had the ELM327 and car scanner app working, so I don't know whether it was talking all along or not.

If I were to do it again my first step would be check the cigarettee fuse.

 

Thanks Aus430,
One of the cig lighter fuses (P-Cig 15A) was blown and I traced it down to faulty cigarette lighter outlet with the ashtray next to the shifter. Had a 20A in there so the previous owner must have known of an issue. Unfortunately this didn't solve my comms issue with my techstream. More investigation needed. Cheers

 

I know you have sorted your issue with your ECU but for any other issues you can use the following websites to help you find which parts are cross compatible. I've had Toyotas for ever and use these sites all the time.
http://www.japan-parts.eu/ Easiest way to use this is to enter your VIN however you can find your car manually. Our market comes under General and the last entry is characteristic and Australia is ARL. The site works for all Toyota and Lexus cars worldwide. You can all enter part numbers to see which other cars carry the same parts. Comes in handy.

https://www.amayama.com/en This lot sell mostly genuine parts and are very popular is Oz to get cheaper genuine bits if you can wait. Great to use if you've found the the local stealership want huge coin for a particular and you can't find an aftermarket equivalent.

Hope that helps.

 

Thank you for the links Macrop They look to be very useful