Tesla Model S 2014 HV Battery issue

[JCM_76]

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 installed it, the car woke up with 13 alerts on it, so I put it on “Service Mode” and take some pictures of the screen (please find them attached to this email),

The more stressful alert for me was: BMS_f080_SW_Int_HV_Disconnect: the BMS has detected that the HV battery pack voltage differs from the sum of the brick voltages, making the HV battery unavailable for charging, driving or supporting the LV battery…

It look like is something is either not connected completely or properly from the battery, or maybe a problem with the HV battery itself?

Can somebody help me, where should I start to solve this problem?

Thanks a lot for your valuable help!

Juan Carlos

 

[JCM_76]

Can anyone confirm the best way to read the isolation resistance from the pack? I was going to read from contactor input voltage B- to the “ground” and then B+ to ground of the pack should I be getting 3,000 Kohms?

See this procedure

 

[5JWX]

Thanks I’ll have a proper look at the document JCM_76

I’ve been trying to work out where the high resistance comes from, but think I’ve been over thinking it!
With a reading of 3000 kohm with contactors open the resistance must be gained by the main BMS module within the battery pack. It’s only measuring to the contactors as they are open so nothing to do with the modules etc. If your battery pack is still out of your MS is there any chance you can measure the isolation resistance from the HV outlet to the body of the battery. I only have approx 40kohm from memory & therefore believe my fault had to be between the HV outlet to the open contactors?

 

[Chickenboy81]

H

 

[Chickenboy81]

Hi guys, I also have bms_f123/bms_w123…13’ MS. I have taken apart my pack checking several hv components for corrosion. I found water/rust in my fuse, as well as a corrosion on several BMS boards on the modules themselves, I also found a corroded ground stud when I tried unbolting it. I am replacing my battery coolant heater as well. My modules all checked out within nominal range and no obvious failed module. I am replacing the BMB near contactors..as well as placing new ground stud on driver side in frunk which is said to make the car inoperable . I would like to open help each other resolve our issues. Unlike you both I have some water ingress through the fuse and the corroded BMS’ were near the fuse in hv pack. I have already checked the fuses in DCDC as well as the fuse boxes in the frunk. I’m curious to see if you checked voltage between the fuse terminals?

 

[howardc64]

Hi guys, I also have bms_f123/bms_w123…13’ MS. I have taken apart my pack checking several hv components for corrosion. I found water/rust in my fuse, as well as a corrosion on several BMS boards on the modules themselves, I also found a corroded ground stud when I tried unbolting it. I am replacing my battery coolant heater as well. My modules all checked out within nominal range and no obvious failed module. I am replacing the BMB near contactors..as well as placing new ground stud on driver side in frunk which is said to make the car inoperable . I would like to open help each other resolve our issues. Unlike you both I have some water ingress through the fuse and the corroded BMS’ were near the fuse in hv pack. I have already checked the fuses in DCDC as well as the fuse boxes in the frunk. I’m curious to see if you checked voltage between the fuse terminals?

Great info. A few questions

- What year is your car?
- salted roads in winter?
- park outside at home or work? How much water does the car see from rain/ice/frost etc.
- which module's BMS boards had corrosion? All towards the front of the car where water ingress is typically the worst?

I've been gradually finding significant water ingress issues on my 2013. Mainly

- windshield water runoff to bulkhead/firewall area. Dumps all over my gen1 DCDC and on top of battery pack on top of the front module hump.
- front wheel liner with softball size holes that sprays water inwards behind frunk
- battery side plastic shield slits completely clogged for 2-3 feet behind both front tires from road water/debris spray
- AC drain outlet on top of battery pack
- coolant reservoir overflow dumps on top of battery pack

Seems like annual cleaning of side breathing vents is highly desirable and periodically opening the battery for water ingress servicing is necessary on this car. Interval depends on how much water car sees and how much salt road use.

 

[Chickenboy81]

Great info. A few questions

- What year is your car?
- salted roads in winter?
- park outside at home or work? How much water does the car see from rain/ice/frost etc.
- which module's BMS boards had corrosion? All towards the front of the car where water ingress is typically the worst?

I've been gradually finding significant water ingress issues on my 2013. Mainly

- windshield water runoff to bulkhead/firewall area. Dumps all over my gen1 DCDC and on top of battery pack on top of the front module hump.
- front wheel liner with softball size holes that sprays water inwards behind frunk
- battery side plastic shield slits completely clogged for 2-3 feet behind both front tires from road water/debris spray
- AC drain outlet on top of battery pack
- coolant reservoir overflow dumps on top of battery pack

Seems like annual cleaning of side breathing vents is highly desirable and periodically opening the battery for water ingress servicing is necessary on this car. Interval depends on how much water car sees and how much salt road use.

I have a 2013 85kwH with original pack. I’ve owned it for 4ish years now and so it’s been in the Midwest since. I am a master’s student so unfortunately it’s been outside for 85% of the last 4 years. Starting from the rear driver corner the modules are numbered 1-16 in a clockwise fashion …modules 7-11 ( 6 total) all have BMS board corrosion or heat damage so all near the hv fuse which experienced water ingress. I have been drying out the hv pack shell while working on the modules . This is my first major problem with the car but if I can fix it I will be sure to do preventative maintenance from this point on.

 

[howardc64]

I have a 2013 85kwH with original pack. I’ve owned it for 4ish years now and so it’s been in the Midwest since. I am a master’s student so unfortunately it’s been outside for 85% of the last 4 years. Starting from the rear driver corner the modules are numbered 1-16 in a clockwise fashion …modules 7-11 ( 6 total) all have BMS board corrosion or heat damage so all near the hv fuse which experienced water ingress. I have been drying out the hv pack shell while working on the modules . This is my first major problem with the car but if I can fix it I will be sure to do preventative maintenance from this point on.

Thanks. All towards the front as noted by @wk057 in this post.

I did 2 DIY maintenance websites on this car. You might find useful as both applies to your car

Tesla LDU

COOLANT DELETE UPDATE! After 10+ years and probably ~$1B spent by all involved, Tesla released Rev U of LDU that eliminates the rotor cooling loop by changing the coolant manifold design. Coolant no longer feeds and cool the rotor. Longevity issues from higher rotor thermals is unknown at this

sites.google.com

Howards Model S

Feel free to reach out to me at [email protected] with any questions. I'm a retired techie that likes to fix things including cars and fix electronic and mechanical things for hobby.

sites.google.com

 

[JCM_76]

Hi,

This is very interesting information that you guys are sharing.

As my HV Battery Pack fuse blown, it is likely that some shorted HV component or its isolation has compromised , so I plan to measure the HVIL isolation of each HV components: a) connected devices to the HVJB (battery coolant pump, AC compressor and PTC cabin heater), b) DCDC (my car have gen2 DCDC that is behind the frunk), c) inverter and d) the rapid splitter connector and cables to the charger as well as to the HVJB. Besides to check the fuses inside the HVJB and the ground studs on the driver side in the frunk, as well as the rapid spplitter.

The BMS of our cars has a very sensitive constant current source indirectly measuring the isolation and I think the moisture, dust or rust can affect such reading triggering the isolation failures.

There's a lot of work to do but I think it worth!

To solve the problem it is importat to investigate its root causes. I am trying to figured out what could be the root causes of the fatal failures: BMS_F080, BMS_F033 and BMS_F123 in my car, and I have two hypothesys:

1) An isolation failure in the PTC cabin heater triggered a warning BMS_W150 that produced an overcurrent compromises the HV battery pack fuse causing to blown when I was driving hard the car, something that resulted in the fatal failures: BMS_F080 and BMS_F033

2) An isolation failure in the PTC affected the precharge circuit inside the pack (pre charge contactor and pre charge resistor) triggering the fatal failure BMS_123

According to the above root-cause analysis, there's something that doesn't make sense yet: why fatal failure BMS_F123 doesn't appears the same day as BMS_080 but six weeks latter?

Please I would appreciate your comments,

Thanks,

 

[JCM_76]

well as placing new ground stud on driver side in frunk which is said to make the car inoperable

Can you please tell me where exactly is located this ground stud? Thanks

corrosion on several BMS boards on the modules themselves

I think this is triggering you fault BMS_u029. Once you fixed it replacing the BMBs, I think that you'll need to reset your BMS to "erase" the fault

 

[Chickenboy81]

Can you please tell me where exactly is located this ground stud? Thanks


I think this is triggering you fault BMS_u029. Once you fixed it replacing the BMBs, I think that you'll need to reset your BMS to "erase" the fault

Remove the trunk liner and you’ll have a ground stud with multiple wires bolted to it both the passenger side rail and driver side rail. They are roughly where I drew circles in my picture included. Even if it looks torqued unbolt it as I did and you may have it snap off due to corrosion like mine.

Yes I am replacing all boards on the modules as well as the main BMB near the contactors as many have warned that bms_u029 is a latched code and is unable to be deleted even with toolbox unless you have internal tesla clearance.

 

[Chickenboy81]

Here is roughly where the ground studs are located.

 

[Chickenboy81]

Hi,

This is very interesting information that you guys are sharing.

As my HV Battery Pack fuse blown, it is likely that some shorted HV component or its isolation has compromised , so I plan to measure the HVIL isolation of each HV components: a) connected devices to the HVJB (battery coolant pump, AC compressor and PTC cabin heater), b) DCDC (my car have gen2 DCDC that is behind the frunk), c) inverter and d) the rapid splitter connector and cables to the charger as well as to the HVJB. Besides to check the fuses inside the HVJB and the ground studs on the driver side in the frunk, as well as the rapid spplitter.

The BMS of our cars has a very sensitive constant current source indirectly measuring the isolation and I think the moisture, dust or rust can affect such reading triggering the isolation failures.

There's a lot of work to do but I think it worth!

To solve the problem it is importat to investigate its root causes. I am trying to figured out what could be the root causes of the fatal failures: BMS_F080, BMS_F033 and BMS_F123 in my car, and I have two hypothesys:

1) An isolation failure in the PTC cabin heater triggered a warning BMS_W150 that produced an overcurrent compromises the HV battery pack fuse causing to blown when I was driving hard the car, something that resulted in the fatal failures: BMS_F080 and BMS_F033

2) An isolation failure in the PTC affected the precharge circuit inside the pack (pre charge contactor and pre charge resistor) triggering the fatal failure BMS_123

According to the above root-cause analysis, there's something that doesn't make sense yet: why fatal failure BMS_F123 doesn't appears the same day as BMS_080 but six weeks latter?

Please I would appreciate your comments,

Thanks,

The day I went to remove my battery approximately 2 weeks after car failure these are the codes that were active. Bms_f123 was not present at the time but I also do not have unlimited access to a lift so my battery has been disengaged since. I plan to reengage the battery this week and hopefully it all works

 

[howardc64]

I have a 2013 85kwH with original pack. I’ve owned it for 4ish years now and so it’s been in the Midwest since. I am a master’s student so unfortunately it’s been outside for 85% of the last 4 years. Starting from the rear driver corner the modules are numbered 1-16 in a clockwise fashion …modules 7-11 ( 6 total) all have BMS board corrosion or heat damage so all near the hv fuse which experienced water ingress. I have been drying out the hv pack shell while working on the modules . This is my first major problem with the car but if I can fix it I will be sure to do preventative maintenance from this point on.

BTW, whats the condition of your one way vents all along the side bottom of the pack?

2014-09-09 21.21.31.jpg (5312×2988) (wizkid057.com)

@wk057 says these gets compromised as well.

 

[Chickenboy81]

BTW, whats the condition of your one way vents all along the side bottom of the pack?

2014-09-09 21.21.31.jpg (5312×2988) (wizkid057.com)

@wk057 says these gets compromised as well.

Surprisingly they looked pretty clean. I have already taken a shop vacuum to the hv pack case but have to clean the contactor area and side vents still since the boards have constant voltage dust/debris can throw them out of wack.

 

[howardc64]

Surprisingly they looked pretty clean. I have already taken a shop vacuum to the hv pack case but have to clean the contactor area and side vents still since the boards have constant voltage dust/debris can throw them out of wack.

Interesting, so your primary coolant intrusion is from near the hump in the front then? Fuse seal failed. AC/windshield runoff also dump in that general front area. Here is stain on top of the dual module hump on my 2013 MS85. Directly above this stain is the hole for the passenger wiper spindle (a couple of things are in between like passenger wiper connector which also has water ingress marks)

13 MS 85 can't go into drive, recent LDU rebuild, some clues from clicking sounds

Here is some analysis of cowl water leak. Didn't fix yet, just analyzing to understand the problem more completely first. Easy hack is to run sealant in all the seams and gaps and may eventually be the only solution available given the design - Most obvious problem is rubber ends on 2 bottom...

teslamotorsclub.com

 

[Chickenboy81]

@JCM_76 there’s an update on this article from EV clinic that I know you are following…bms_f123 apparently is PERMANENT. They suggest as they did with bms_a029 previous article that the main BMS can be reprogrammed. This model s appears to be in worse water ingress condition than any of our cars nonetheless we all share the same error code.
BMS_f123 – EV Clinic

 

[JCM_76]

Thanks @Chickenboy81 very important information... They said that once this kind of failure has been detected, the battery pack must be dismounted inmediatelly to fix the problem, due to the risk of total damage... at what kind of damage could be our cars be exposed?

My car has only BMS_F123, i am monitoring almost every day the internal cell voltage and voltage umbalance between cells, everyrhing looks OK. This is how my cells voltage looks right now:

 

[JCM_76]

@Chickenboy81 EV Clinic staff says about BMS_F123:

You must fix cause of issue [low HV internal isolation] then send us BMS for reprogramming

I don't know if change the BMS instead of reprogramming it will solve the problem... what do you think?

 

[JCM_76]

Hi,

Yesterday I put the car in service mode plus and see an internal isolation value of 3.6MOhm... fault f123 disappeared, but f036 apperead (HIVL issue), so I moved my case to this thread.

Thanks,

 

[Gareth676]

Very new to this game but my 2016 Model S (UK variant) gave similar messages in some respects with warnings about no suspension, Cant Start, low voltage, etc. After a hard reset, these messages disappeared and I was left with a warning message that my 12v Battery voltage is too low and I should take to a Service centre for replacement. In all other respects the car operates and drives fine. This message will not cancel until battery is replaced. In looking up how to do this on YouTube, a couple of videos warn of dire consequences if the high voltage connector is not disconnected BEFORE disconnecting the 12v Battery. I'm just wondering if that was done before you removed your battery - apparently it wrecks the software if you don't, which maybe results in all kinds of spurious and possibly erroneous error codes? Just a thought.