HV isolation fault of batterie

[Martin_Schmid]

Hello,

To start off, I have bought a broke down Model S 85 intending to repair it, since the workshop owner the old car owner went to told me, that a battery block was dead.

I am a certified mechanic with HV-Tools to meet the precautions of opening a HV car battery, so I didn't think it would be to much effort.

After testing every block on its own without finding a faulty one, I discovered that the 400V fuse was dead. So I bought one of these, packed everything back up and that should have been it. The car even worked at that point, but with somewhat limited power. After a testdrive the power got worse by the km. Now it's back to not starting.

Since water got in the battery when opening it, I thought that was a problem, even though I dried it out and used an heater for 15h to evaporate all rests. The resistance between the fuse and the aluminium casing is 5.6 M Ohms, which I have read in a different forum was enogh.

Now the question, is there a tool I need to reset all Isolation errors or do you guys know any other cause to my problem?

I have added the error list. I apologize that it is in german, but the numbers should help.

 

[Coloman]

Hello Martin I have almost an identical issue. Replaced fuse and dried out front battery cover because there was water inside. I now have f_123 iso fault. Did you ever find out what your problem was?

 

[Martin_Schmid]

Hello Martin I have almost an identical issue. Replaced fuse and dried out front battery cover because there was water inside. I now have f_123 iso fault. Did you ever find out what your problem was?

Hey, unfortunately not
In this thread of a german forum MCU2 Fehlerspeicher löschen i have gotten the answer, that the battery is most likely dead.
Since I first took it on an test drive, with still slightly wet battery, the internal isolation was still too bad and the car saved this error internally. As Sparbine said in the other forum, it is most likely not possible to delete this error and even a tesla workshop would probably sell you a new battery.

So sadly I couldn't fix this mess and now still have a broken Model S standing around, so if you somehow find a working solution, please consider sharing it here.