I thought I’d retire in a cottage of sponsored hybrids before some Model 3 with a defective out-of-warranty powertrain came into my LAB. A failure caused by mechanical damage to the battery case at high speed on the highway. On the road, the driver picked up a piece of metal (not an n47 chain) with the right front wheel, which hit and broke the battery case in an area where it can’t even be seen behinde wheel liner. After a month of driving, due to the penetration of moisture, water, rain and other leaking oils (Punto, Passat, Golf…) the Alert that 400v is touching chasis came on, in practice called “Iso fault”. After starting the warranty process at the authorized service center because the hole was not visible, after additional checks and almost replacing the battery in the warranty, a problem was noticed and the warranty was rejected. Mechanical damage of any kind is not part of the warranty!!! There is a tolerance of case bending to the inside up to 8mm, but case penetration and water ingress are not part of it. The preliminary estimate for the battery change is €11,800, which is cheaper than the 651, n47, n57, b47, 654 diesel engines, but certainly too much for anyone to give up on that much money at once. Our task was to solve the battery without dismantling, patch the hole and dry the closed battery without taking it off the car… that means absolute improvisation and tool making with solving the problem 100%. First, we opened the umbrela valve vents on the battery, which has 2, then we made an artificial heated “greenhouse” around the battery and an irradiation system to extract moisture. We let the system run for 14 days for 10 hours to heat the case to 48 degrees while the rest of the “cooker system” does its job to extract moisture. After 2 weeks of labor Isolation returned to 4.8Mohm before and after the contactor… that means the battery is finally saved. However, repeated isolation breaches have left the security system in a locked state with error BMS_a027, an error that, with its number 027, oozes trouble as it is a FATAL FLAG (latching alert) to protect the system from further or larger problems. It limits the system permanently and the service ToolBox does not have a function like for Model S and X, which is called “ISO Counter Reset”, this time for Model Y and 3 this function has been moved to the Tilburg refurbish battery center where the battery repair team resets on the bench via CAN BUS. We solved the problem and the consequences, but now the most difficult part remains, how to clean the firmware safety system. We work for the first time, we read the processor for the first time, which fortunately does not have a locked JTAG, and we look for the HEX FLAG in the sea of data. After a few hours of work, we cleared the FLAG, redeployed the system again and BMS removed the error. VOILA, the battery was solved and the owner was saved by a 3rd party solution for the first time in the world. It means another example, that it is not necessary to change the entire battery, but to solve the problem in segments.
HRVATSKI:
Tesla Model 3 LR – NEISPRAVNA BATERIJA NIKAD SE NE MIJENJA CIJELA – Mislio sam da ću otići u mirovinu u vikendici sponzoriranih hybrida prije nego mi dodje neki Model 3 sa defektnim pogonom izvan garancije. Kvar koji je uzrokovan mehaničkim oštećenjem baterijskog kućišta pri većoj brzini na autocesti. Vozač je na cesti pokupio desnim kotačem komad metala (nije n47 lanac) koji je lupio i razvalio kućište baterije u zoni gdje se ne vidi ni na dizalici jer bas tu pokriva PVC wheel liner. Kroz mjesec dana vožnje zbog penetracije vlage, vode, kiše i ostalog ulja (punto, passat…) upalila je se greška da 400v probija na šasiju, u praksi zvan “Proboj izolacije”. Nakon započete garancije u ovlaštenom servisu jer rupa nije bila vidljiva, nakon dodatnih provjera i skoro pa zamjene baterije u garanciji uočen je problem i garancija je odbijena. Mehanička oštećenja bilo kojeg oblika nisu dio garancije!!! Postoji tolerancija udubljenja kućišta do 8mm ali proboj kućišta i voda nisu dio toga. Predračun za izmjenu je 11800€ što je jeftinije od 651, n47, n57, b47, 654 i ostalih nikad ništa motora, ali svakako prevelika svota za bilo koga i čega. Zadatak nam je bio da riješimo bateriju bez demontaže, zakrpamo rupu i osušimo zatvorenu bateriju… znači apsolutna improvizacija i izrada alata a da se problem riješi 100%. Prvo smo otvorili oduške na bateriji koji ima 2, zatim smo napravili umjetni plastenik oko baterije i sustav ozračivanja za izvačenje vlage. Sustav smo pustili da radi 14 dana po 10 sati da zgrije kućište na 48 stupnjeva dok ostata “pastenika” radi svoj posao. Nakon 2 tjedna izolacije se vratila na 4.8Mohm prije i poslje kontaktora… to je to baterija spašena. Medjutim uzastopni proboj izolacije je ostavio sigurnosni sustav u zaključanom stanju sa greško BMS_a027, greška koja svojim brojem 027 odiše problemom jer je to FATAL FLAG da zaštiti sustav od daljnjih ili većih problema. Limitira sustav trajno i servisni ToolBox nema funkciju kao za Model S i X koja se zove “ISO Counter Reset” ovaj put za Model Y i 3 ta funkcija je preseljena u Tilburg refurbish battery centar gdje ekipa koja reparira baterije resetira na stolu preko CAN BUS. Mi smo riješili problem i posljedice ali sad je ostao najteži dio, kako očistiti firmware safety sustav. Prvi put radimo, prvi put čitamo procesor koji sva sreća pa nema zaključan JTAG i tražimo HEX FLAG u moru podataka. Nakon par sati posla očistili smo FLAG, napravili redeploy sustava opet i BMS je maknuo grešku. VOJLA, baterija je riješena i vlasnik spašen 3rd party riješenjem po prvi put u svijetu. Znači još jedan primjer, da nije potrebno mjenjati cijeli bateriju već riješiti problem u segmentima.
Errors: BMS_a027 , BMS_f027, BMS_w027, BMS_a170
Part number: 1104423-00-N, 1106394-01-H,
Processor: TMS320LS , SPC5746CSMKU6 1N84S
Tesla OEM: 11800€ (inc VAT)
EV Clinic pricelist:
*diesel is cheaper – 69000€
*hybrid is better – 96000€
*ev is better – 1200€
