After 7 years of ownership and 11 different diagnosis / fixes from the dealership, I am still facing the dreaded battery drain issue. I've gotten the battery replaced probably 7 or 8 times, the alternator replaced, and a new Network Gateway ECU per the problematic TSB back in 2017 yet I am still having issues with the battery drain. Most recently, the battery barely had enough juice to start the car so I took it into the dealer post warranty.

They had the car in the shop for 3 days and diagnosed each of the fuses and found some parasitic drain tied to the Network Gateway ECU and wanted to charge me $2300 to replace it. I told them that they replaced that specific part a few years ago but it is still an issue today so they should at least help me cover it under a part warranty, but they wouldn't do so because the part numbers were different. I was extremely fed up with this resolution and called Lexus Corporate. They assigned me a nice gentleman who went through with the service advisor and they offered to buy me a battery tenderizer to keep the charge up. This wouldn't work because this is just a band-aid to the overall problem. Lexus Corporate has now agreed to schedule an appointment with the Field Technician Specialist but due to the corporate travel ban, they can't schedule me one until it is lifted.

Does anyone else still have this issue? Did they update the Network Gateway ECU to a new version / part number that actually works? I just want my car to be reliable when it starts...

 

Since they agreed to send a technician thats your best bet. What part did they install when they did the TSB in 2017. Furthermore it looks the like the ECU only cost $130, where did they get $2300 from?

 

was wondering how long it takes for your battery to drained? like from you driving and then parking your car till the next time you come get you car and its dead?

 

I think most are going to zero in on this part of your statement as if the TSB directs them to install the latest and greatest ECU, then why is there a different part number now?
The TSB should have been updated with the most current part number. If the part number changed after the TSB, that means the TSB part didn't work and revised part needed to be created.

Do you know what part number you have installed and which one they want to install?

The battery tender isn't really a solution if the vehicle genuinely has a parasitic draw...the tender will just mask the problem.