LS400 ECU compatibility information

[Razor61]

Some information on ECU compatibility, bear with it because it will make sense at the end I hope😀 and maybe help someone who has a duff ECU or an ECU with the capacitor issue and can't find the exact one to replace it.

I have been trying to find an ECU for my 1996 LS400 (1995 model year) - part number 89661-50310. I purchased the needed capacitors with a view to replacing them in my current ECU but after examination the ECU was in pristine condition so decided to leave it alone as it functions fine. But as I have already purchased the capacitors I decided to try and find a used ECU to play with and replace the capacitors, plug it into my car, see if it works and if it improves anything on the car. There are a couple of ECU's part number 89661-50310 for sale but the price is around £180 which I don't really want to pay just to play with and have a try doing the capacitors. I looked on Amayama and for my car it lists ECU part number 89661-50351 as a substitute, as illustrated below.

These ECU's - part number 89661-50351 - are more plentiful and cheaper at £60 - £70 which is more like what I'm happy paying but I wasn't 100% happy about buying one because there is no guarantee it will actually work. My question then was, how can I find out for sure if this ECU will work with my car? Amayama lists it as a substitute but.............. 

The best people to tell me are Lexus themselves so I contacted Lexus Customer Relations, explained the situation, supplied vin etc. and asked if ECU part number 89661-50351 is compatible for my LS400. It turns out it is and the reply from Lexus is below. Amayama is correct with the ECU substitute for my car so I assume it will be correct for others.

Reply from Lexus:

Thank you for your email about your vehicle.

Yes this part is a direct supercession from 89661-50310 to part number 89661-50351. Part number 89661-50351 can be used in this vehicle.

[cruisermark]

HI

Maybe this thread will shed some light:

 

[Razor61]

39 minutes ago, cruisermark said:

HI

Maybe this thread will shed some light:

 

Cheers, I'm all sorted now though. Bought a 89661-50351 ECU to have a go with and when I fancy dismantling the glove box/s again I'll plug it in.

[Malc]

On 12/20/2019 at 11:58 AM, Razor61 said:

when I fancy dismantling the glove box/s again I'll plug it in.

do please keep us in the picture with all this progress

Thanks

Malc

[Razor61]

So took the plunge and fitted the 89661-50351 updated ECM/ECU today, took an hour to do with glove box removal, swop ecu, re connect Battery, test it works, refit glove box and everything is fine. Car started and took it for a short run to check everything works.

If anyone has a duff ecu and is struggling to find the exact one then an updated one may be the answer, Amayama was correct with an alternative one for my car but you can double check with Lexus UK to be sure as I did.