Car died. BMS errors f123, w123, w073, w035, w142, w158

[brainhouston]

Unfortunately my 2016 MX 90D decided to surprise me with these errors
We had a few days of cold/snow days and the car did fine.
Last couple of days its been above freezing and everything already melted.
I drove the car in the morning, then parked on driveway. Few hours later, started ok and went into drive, then few seconds later got:
Bms_w035 (Vehicle may not restart)
I occasionally had this error over the last 10k miles only during pre-heating and chuck it up to software as mentioned here:

AP1 ONLY Please -- life after 2018.50.6

from my experience with .28 the alternate routes only show briefly if you're already in motion then default to one of them. if you navigate while stopped you'll see the alternate routes to choose from.

teslamotorsclub.com

However this time, few seconds later i got a slew of others (as in title).
Car was still in drive so I drove it few feet forward and back, parked it, restarted and this time it wasn't moving.

I have access to diagnostic/developer modes, so here's what's in there:

bms_w035_sw_isolation
bms_f123_sw_internal_isolation
bms_w123_sw_internal_isolation
bms_w073_sw_unexpctd_hv_sys_bhvr
bms_w142_sw_isolation_degradatio
bms_w158_sw_low_isolation_wrn

All these look pretty scary and seem to point to inside the battery but i'm having hard time finding any cases with some of these errors, esp w073...

Cell voltages look ok

There're lots of tags i can look at in diag mode but not sure what they all mean..
However the Isolation just says zero, which is concerning..

I honestly not sure where to start... don't want to pull the battery unless im 100% sure the fault is inside...
I found a mention of f123 error and that its pretty serious, how true is it?

Tesla Model S 2014 HV Battery issue

Hi, I have a Model S 2014 P85+ Last Monday I was driving it near from my house in Guatemala, but the car suddenly stoped with the warning: “Unable to drive, supply voltage too low”… I thought that would be a 12V battery failure, so, on my own, I replaced it for a new one. Yesterday, after...

teslamotorsclub.com

Edit: car is salvage and rooted, Tesla is locked out so i won't be taking it to SC anytime soon nor planning on it
Have put 10k miles on it since i fixed it in Oct 22

@wk057 I know you're busy but would appreciate any insight if you're familiar with these errors

 

[wk057]

Isolation resistance 0 is really really bad. But since it's an issue during heating, it's probably just the pack heater failed and is shorting HV to chassis.

 

[brainhouston]

Isolation resistance 0 is really really bad. But since it's an issue during heating, it's probably just the pack heater failed and is shorting HV to chassis.

Agree. My car is always in Range mode tho and it was like 35F out, pretty sure Batt heater doesn't come on at all unless BMS does some checks...
Could be cabin heater i guess..
I'll try checking all external HV components but i'm wondering why its reporting Internal Isolation? Can it still be external with those errors?...
Thanks wk!

 

[ATPMSD]

12V battery problems will cause all kinds of error messages. “Vehicle may not restart” is a pretty good indicator of this. If you can get the car to wake up, turn on Sentry mode and turn off all exclusions. If you do not have Sentry mode, turn on camp mode before existing the car after driving. This will keep the car awake and thusly the 12v system will be powered by the DC-DC converter, so the car should then remain drivable. Then replace the 12v battery.

It certainly could be something else, but the 12v battery is where I would start.

 

[brainhouston]

12V battery problems will cause all kinds of error messages. “Vehicle may not restart” is a pretty good indicator of this. If you can get the car to wake up, turn on Sentry mode and turn off all exclusions. If you do not have Sentry mode, turn on camp mode before existing the car after driving. This will keep the car awake and thusly the 12v system will be powered by the DC-DC converter, so the car should then remain drivable. Then replace the 12v battery.

It certainly could be something else, but the 12v battery is where I would start.

Appreciate the help but i don't think its 12V battery..
In my screen shot u can see a code for "12V not supported" cause DC-DC was turned off (all HV was off)
However my car stayed powered up for a while like couple of hours while i was looking around for codes n such, this was all running off 12v
I'll charge it up n test it for sure but i think the issue is HV. I just need to figure out if its inside the HV or outside like heaters...

 

[NewbyMaybe]

If the 12v is not new and is exposed to freezing then it's worth bypassing it.

 

[brainhouston]

Update: no good news, still have f123/w123 errors, car won't even turn on with brake press

Car sat for about 5 days with 12v/fireman loop disconnected (didn't have time)
My 12v battery is fairly new, has sticker with 12/2020 on it

I tested it with battery tester n it showed 392CCA, 100% health. I charged it up n put back in the car.
All 12v electronics work but i still have the codes. Tried scroll wheels + brake reset, nothing..

I poked around more in dev/diag menus n isolation seems ~3.3MOhms
From my research it seems to be good, not sure what the tag difference is to previous one i posted or maybe zero isolation went away or maybe a glitch??

Seems isolation went up a bit while browsing the menus.. 3160 > 3320, or maybe just measuring noise??
Does anyone have this value from their car? im curious how it compares...
Right now car only has f123/w123 flags set

Anyone know if these are latched codes and need clearing or will they go away once the issue is fixed?

I found a couple of post about how to reset BMS codes but i don't know what hardware/software i need to send these commands... anyone can clarify?

No need to buy random diag tools or pay anyone ridiculous amounts of money to fix this.

Fix it by sending these CAN messages with any CAN transceiver on the powertrain CAN:

CAN_BUFFER_ITEM bms_iso_reset[] = {
    { .id = 0x602, .len=8, .data.u8 = { 2,0x27,05,00,00,00,00,00 } },
    { .id = 0x602, .len=8, .data.u8 = { 0x30,0,0xA,00,00,00,00,00 } },
    { .id = 0x602, .len=8, .data.u8 = { 0x10,0x12,0x27,0x06,0x35,0x34,0x37,0x36 } },
    { .id = 0x602, .len=8, .data.u8 = { 0x21,0x31,0x30,0x33,0x32,0x3D,0x3C,0x3F } },
    { .id = 0x602, .len=8, .data.u8 = { 0x22,0x3E,0x39,0x38,0x3B,0x3A,0x00,0x00 } },
    { .id = 0x602, .len=8, .data.u8 = { 0x04,0x31,0x01,0x04,0x0A,0x00,0x00,0x00 } }
};

Then figure out what's actually causing the isolation issue and fix that (HV blade seal, pack heater, etc). Repeatedly "fixing" this error with the above CAN messages (or with third party tools) is NOT the correct way to fix this. The car is throwing this error for a reason, and that physical issue needs to be corrected. Otherwise the car can have serious issues, including ones that can result in injury/shock/etc. There's isolation failure detection in the hardware for a reason. Don't ignore this, and don't just reset the error without actually finding and fixing the underlying issue.

In my experience the most common problem is the pack heater corrosion causing isolation failure via the coolant. Second is water ingress into the battery pack HV connector due to dry-rotted rubber seals. Beyond that, could be a bunch of things and you'll need special equipment to track that down (megaohm HV isolation testing equipment to check each component).

So Tesla use UDS over CAN BUS to handle ECU diagnostics.
Tesla have multiple buses which can be accessed from the diagnostic connector under the middle screen. For this we want CAN BUS 3 (the drivetrain CAN) at a speed of 500kbps

You can use any cheap CAN BUS analyser to send and read these messages.

They have a login procedure for UDS which is the same seed and key for all cars luckily.

Below is an example of the CAN frames required to clear the BMS stress on a Model S, I've included a comment to show what is going on too...

Direction	Can ID	Data	Comment
you send to car	0x602	02 10 03 00 00 00 00 00	Tell the car to start diag session, note the 10 value for UDS Session Start
car responds with	0x612	02 50 03 AA AA AA AA AA	Response contains 50 (10 + 40)
you send to car	0x602	02 27 05 00 00 00 00 00	start a secured session, note value 27
car responds with	0x612	10 12 67 05 00 01 02 03	all good, note 67 (27 + 40). Start of seed
you send to car	0x602	30 00 00 00 00 00 00 00	flow control message, meaning ok ready for more data
car responds with 2 frames, 1st	0x612	21 04 05 06 07 08 09 0A	more of the seed
2nd frame from car	0x612	22 0B 0C 0D 0E 0F AA AA	final part of seed
you send to car	0x602	10 12 27 06 35 34 37 36	thanks for seed, here is the key
car responds with	0x612	30 00 00 AA AA AA AA AA	flow control, car is ready for more data
you send to car	0x602	21 31 30 33 32 3D 3C 3F	first part of key
you send to car	0x602	22 3E 39 38 3B 3A 00 00	second part of key
car responds with	0x612	02 67 06 AA AA AA AA AA	All good, note the 67 (27 + 40), logged in basically
you finally send	0x602	04 31 01 04 06 00 00 00	the thing you actually want to do, 06 means reset contactor stress.
car responds with	0x612	05 71 01 04 06 01 AA AA	Car completed the task, note the 71 (31 + 40) and the 01 confirmed completed.

So that is one example of a BMS stress reset, below are the others that I know (just replace the final send with these)...

Clear stress	04 31 01 04 06 00 00 00
Reset WOT	04 31 01 04 07 00 00 00
f163	04 31 01 04 02 00 00 00
f153	04 31 01 04 05 00 00 00
f152	04 31 01 04 04 00 00 00
Open Positive Contactor Reset	04 31 01 04 02 00 00 00
f026	04 31 01 04 0A 00 00 00
w026	04 31 01 04 01 00 00 00
? w023	04 31 01 04 02 00 00 00

If anyone knows anymore then please add to this list to help the community out.

Hopefully this helps people out without the need to spend thousands on diag equipment.

Sorry for the long post and appreciate all the help!

 

[ATPMSD]

It seems suspicious to me that in the first screen it shows the BMS status as Fault and on the second the BMS fuse is unknown. Perhaps the issue is with the BMS module itself?

 

[brainhouston]

The way i understand it is BMS fuse is the Pyro fuse in the pack?..
BMS status is just saying that there's a fault, in my case w123/f123
But i do think its possible that actual BMS board could be faulty.
I found couple of instances (here n on reddit) with same codes n bms pcbs were replaced...

This brings up another question, can BMS board be simply swapped with other new/used?? or does it need some data copied over...

 

[ATPMSD]

can BMS board be simply swapped with other new/used?

In some cars you have to drop the HV battery to swap out the BMS board.

 

[brainhouston]

In some cars you have to drop the HV battery to swap out the BMS board.

Correct n def the case for X n S models
My question was whether it needs to be paired with cells somehow or will new board simply auto learn ?
I seem to recall wk057 saying something about erasing BMS history is bad so that implies that BMS has some memory?..

 

[wk057]

You can't reset f123/w123. These are the result of an internal isolation error, 99.9% of the time meaning water inside the battery pack. (Sorry, I didn't catch you'd noted these codes when I replied previously, I must have skimmed too quickly.) External isolation is separate (and can be measured separately most of the time as well).

Unlikely the BMS mainboard is bad.

Fuse type unknown is normal.

 

[brainhouston]

You can't reset f123/w123. These are the result of an internal isolation error, 99.9% of the time meaning water inside the battery pack. (Sorry, I didn't catch you'd noted these codes when I replied previously, I must have skimmed too quickly.) External isolation is separate (and can be measured separately most of the time as well).

Unlikely the BMS mainboard is bad.

Fuse type unknown is normal.

Thanks, appreciate ur wisdom as always!
So, how do u go about these errors in ur experience? if i open up the pack n its possible to get rid of water n cells are good, will these errors go away?
Or do i need new pack no matter what?

 

[Electric700]

Agree. My car is always in Range mode tho and it was like 35F out, pretty sure Batt heater doesn't come on at all unless BMS does some checks...
Could be cabin heater i guess..
I'll try checking all external HV components but i'm wondering why its reporting Internal Isolation? Can it still be external with those errors?...
Thanks wk!

Sorry that happened. I think you should not use Range Mode; this way the main battery can be properly maintained temperature-wise.

What does Tesla say? The Tesla location is fully reviewing everything with your vehicle?

 

[brainhouston]

Sorry that happened. I think you should not use Range Mode; this way the main battery can be properly maintained temperature-wise.

What does Tesla say? The Tesla location is fully reviewing everything with your vehicle?

Thanks. Can u elaborate on use of Range mode?
I've done lots of searching here when i started driving this car n couldn't find definitive answer whether to use it or not...
Since the temps here in PDX area barely ever drop below freezing i chose to leave it in Range mode (was already set when i got the car from Cali)

I'm not taking the car to Tesla yet, wanna try figuring out things myself first (DIY soul here) n also its rooted so gonna have to undo that before taking to SvC..

FYI, i got some updates but don't have time rn. Will update this later...

 

[Cheese Guy]

Thanks. Can u elaborate on use of Range mode?
I've done lots of searching here when i started driving this car n couldn't find definitive answer whether to use it or not...
Since the temps here in PDX area barely ever drop below freezing i chose to leave it in Range mode (was already set when i got the car from Cali)

I'm not taking the car to Tesla yet, wanna try figuring out things myself first (DIY soul here) n also its rooted so gonna have to undo that before taking to SvC..

FYI, i got some updates but don't have time rn. Will update this later...

Some info from our good buddy Bjørn.

 

[brainhouston]

You can't reset f123/w123. These are the result of an internal isolation error, 99.9% of the time meaning water inside the battery pack. (Sorry, I didn't catch you'd noted these codes when I replied previously, I must have skimmed too quickly.) External isolation is separate (and can be measured separately most of the time as well).

Unlikely the BMS mainboard is bad.

Fuse type unknown is normal.

So you CAN actually reset f123/w123 errors
LayZ remotely reset them for me since Isolation showed >3 MOhms and I wanted to try this anyways to see if errors come back

Car went into Drive and i was able to drive it to shop but errors came back after few minutes of driving
This time i got External Isolation first then also got Internal...
Isolation values were dropping as i was driving. After 10min when i arrived it was down to 20kOhms
However i think you're correct that i got water in the pack, nothing leaks out but i can see moisture on the inside of front valves

I'll post more details in next post...

 

[brainhouston]

Current update...

After the car sat for a couple of weeks, i saw isolation high/normal (screenshots in above posts)
FYI, these 2 tags are slightly different in values but sometimes the same:

Contacted LayZ n he said he can reset f123/w123 errors (only active errors i had at this time).
Did the reset, car turned on, contactors closed, was able to go in D and R. Still in the garage.
With contactors closed (normal based on research):

Few hrs later when i had time, i drove it outside for a test. Range mode n cabin heat off.
As soon as i left my street, BMS_w035 came on.. So i decided to drive to my family shop, 10min away

No other errors at this time. Got bunch of errors few min later...
While driving was watching diag screen, iso kept fluctuating/dropping..
Few min later:

10min when arrived to shop:

Car obviously didn't restart...
Active/inactive errors at this time:

Its possible that i do have external isolation but also could be that since contactors were closed it miss-detected... not really sure yet...
After the car sat for about 30min in the shop:

So, it seems isolation drops when car is driven but goes up when parked... this is gonna be challenging to find...
Let the car sit for a day to dry.
Put it on the lift n didn't see any damage or obvious water ingress, except this:

One of the the 4 middle (guides?) where bolt goes is not flush but seal behind seem to be engaded. Peeled the seal off a bit with pick tool n its wet behind the seal but not dripping... Tried tightening (after removing bolt), moves maybe a quarter turn... don't have the right tools for this... (if anyone knows let me know).
Opened up the only cover i can access rn in the front (orange), nothing dripping but see droplets:

Not sure if battery supposed to be fully dry or some moisture is acceptable??
I did see this tag earlier, and pretty sure @Recell mentioned they look at this during battery rebuilds..

Anyone know how BMS calculates this??

I guess its safe to say i have some water in the battery n plan to take it down n investigate... Will start with removing side covers n looking at valves...
Currently waiting on 5pt socket to remove Pyro cover n see if moisture is there.

Also, found this site that has some definitions for errors but its not matching up my experience so maybe old data or for diff version?

BMS_f123_SW_Internal_Isolation

 

[Recell]

While it's difficult to determine the exact extent of the internal water damage without the pack in hand, the repeated plunge in isolation resistance any time the pack is moved or disturbed, the quick reveal on the forward umbrellas combined with the MCS water accumulation levels, are definitely NOT a good sign and the damage may well be extensive. (note: our earlier reference to umbrella inspection and replacement was related to dust and dirt build-up in the rails/umbrellas vs. actual water accumulation and repeated isolation faults)

The challenge is going to be the extent of the repair, if any, and these internal isolation issues tend to have a binary outcome - either a *possible* fix OR an unsalvageable pack that can't be re-certified. We've had this same issue present itself several times over the last few weeks with the recent flooding in California. There's little that can be done without first dropping and opening up the entire pack, and if turns out that the pack isn't salvageable (the more likely outcome) there may well be more cost effective replacement options closer to home for most owners. So even though a fix is a high-reward outcome and full replacement packs are expensive, we've been reticent to encourage owners to send in their pack in these situations. It's a tough one.

 

[wk057]

While it's difficult to determine the exact extent of the internal water damage without the pack in hand, the repeated plunge in isolation resistance any time the pack is moved or disturbed, the quick reveal on the forward umbrellas combined with the MCS water accumulation levels, are definitely NOT a good sign and the damage may well be extensive. (note: our earlier reference to umbrella inspection and replacement was related to dust and dirt build-up in the rails/umbrellas vs. actual water accumulation and repeated isolation faults)

The challenge is going to be the extent of the repair, if any, and these internal isolation issues tend to have a binary outcome - either a *possible* fix OR an unsalvageable pack that can't be re-certified. We've had this same issue present itself several times over the last few weeks with the recent flooding in California. There's little that can be done without first dropping and opening up the entire pack, and if turns out that the pack isn't salvageable (the more likely outcome) there may well be more cost effective replacement options closer to home for most owners. So even though a fix is a high-reward outcome and full replacement packs are expensive, we've been reticent to encourage owners to send in their pack in these situations. It's a tough one.

All of this ^

----

Based on everything noted, the pack is 99% likely water damaged and at this point unrecoverable. Resetting f123 will do nothing to fix this, either. (I also posted how to do this in another thread somewhere, btw... don't pay anyone to do this. EDIT: Correction, BMS_f123 is not the resettable isolation error, that's BMS_f027... BMS_f123 is NOT resettable, so still don't pay anyone to do this haha)

While driving was watching diag screen, iso kept fluctuating/dropping..

This is almost certainly the result of water that has settled physically moving while you drive. Stop trying to drive it. If you're hitting 20 kOhm of iso (and keep in mind that's an average over a multi-second measurement), that's almost a direct short of HV to chassis. Just stop trying to use this car. That's actually well into unsafe-to-touch territory. I wouldn't even let my crew disassemble a pack with that low isolation resistance since it makes the unsafe-to-touch areas effectively the entire chassis. I'd maybe do it myself, very carefully because I've done hundreds of packs, in full HV protective gear if absolutely needed, but most likely would just dispose of it instead since in our experience there's not much to be recovered from such packs, if anything.

Sorry can't be of more help here, but a pack replacement is going to be your only option. Water damage, even if "dried out" leaves lasting damage to the cells... especially since you've been trying to utilize it despite the issue. Even if you manage to clear the isolation problem both physically and electronically, the pack won't last very long, if at all.

Tesla's refurbished replacement is your best option for water damaged packs, since they don't care about the condition of the core pack as long as there is a core pack. So I'd suggest going that route. Otherwise I'd just scrap the car and move on.

057 won't be able to give you much of anything for your core pack if water damaged, and I'd guess Recell would be in roughly the same boat there with their replacement offerings.

It's worth emphasizing: This pack is NOT safe to dismantle, and I would NOT suggest doing so.