TMS P85 motor humidity: high voltage câbles seal leak, error GTW_w176

[OttoPV60]

Hello everyone,

Here is my problem:

26/12: my Tesla model S gave me error messages: GTW_w018 and w157: reduced electrical power; GTW_w174 and w177: provide battery replacement based on voltage (12v); regenerative braking off; GTW_w017 reduced power.

But she continued to drive.

Then on 28/12: it drives, I stop to buy bread and when I want to restart, then it no longer starts: DI_w127: parked carefully, BMS_f027 and GTW_w176: impossible to start.

It is no longer guaranteed, as it was registered in 2014.

Call from the tow truck, direction the Tesla garage.
The garage told me that it had disconnected the + and - of the motor (power side) and discovered moisture there. This is due to the seals on the DC cables which are HS.

By the way, the courtesy vehicle at Tesla is free during the warranty period, then it's 130€ per day. I should have taken advantage of it more often when it was guaranteed.

To change the seals, the cables must be replaced because they are crimped at the factory. The seals are not replaceable because they are blocked between the crimped terminals. (1,000€)

In addition, the humidity having entered the engine (rain), the engine block must be completely replaced. Standard exchange. There is a current leak, visible on the megger (mega ohm meter). Motor insulation fault which causes all the faults mentioned above to appear. (6 500€)

So an estimate of €7,500.

I ask them: is it possible to try to let the engine dry
Answer: yes, we can try but if it works, I will have you sign a liability waiver in the event of electrocution because there has been water observed in the motor. I say ok.

The estimate is updated to 1500€ for the cables, I validate.

A week later, he calls me: still the same, current leakage fault. In addition, the estimate and redone: €8,000

I ask where the extra €500 comes from: answer: we have to look. Do you still have the quote for €7,500? we no longer have the initial (dematerialized) quote.
No luck, me either because I did not print it.


I ask to see the car in the workshop. I note that there is nothing openable on the motor to dry it, apart from 2 holes DN 20 (the penetration of the + and - cable). There is an inspection hatch (~10cm by 5cm) in the center of the engine block but it has not been opened… (it does not help drying in my opinion)

I ask if a second-hand engine is possible: answer: it is already a reconditioned engine in the estimate.
Surprise on my part.
But hey, the quote is in English (Tesla Lille), it may have been written but I'm not good at English.

So, I ask to have my engine reconditioned. Answer: it is an operation carried out in Amsterdam but only for Tesla, internally. Not for customers. At the garage, we only do standard exchanges of the entire engine block.

Info: A reconditioned engine is guaranteed for 4 years.

I indicate that: My engine block was replaced 2 years ago, free of charge because the car was still under the 8-year warranty. Answer: He tells me that it was also a reconditioned engine but that it does not benefit from the 4-year warranty because it is only the remaining time of the car under warranty that is taken into account.

This is where I am.

I'm thinking of bringing the vehicle back to my house to actually try to dry it out.
I hope to be able to send a flow of warm air into one of the DN20 holes + put a heating blanket over the entire engine block for 1 week.
I also need to find a megohmmeter to be able to test before-during and -after.

When do you think ?

 

[xcyber]

In my opinion, it is not the humidity present but the degradation of insulation of components in the motor unit, that is giving you poor Megger readings. It is best not to risk short circuit and fire when the motor loaded. I think a 4 year warranty motor is a good option. It sucks but honestly this is not a DIY. Don't risk your life.

 

[KalJoMoS]

You have mentioned that Tesla is offering a reconditioned engine with 4years warranty. Then why the new (reconditioned) engine replaced two years ago can’t be replaced under their warranty?

 

[OttoPV60]

In my opinion, it is not the humidity present but the degradation of insulation of components in the motor unit, that is giving you poor Megger readings. It is best not to risk short circuit and fire when the motor loaded. I think a 4 year warranty motor is a good option. It sucks but honestly this is not a DIY. Don't risk your life.

Thank you for your interest.

If I dry it and the megohmmeter (Megger) reads infinity after drying: that indicates that the problem was due to humidity.
Why would there be a fire hazard please ? do you think corrosion ? but I think that : if there is corrosion, the default will remain visible to the Megger and therefore the engine will have to be changed. no ?

If drying does not change the current leak: this will prove that it was not due to humidity. in this case, I will have to change the engine.

for 6 500€ I really want to try

 

[OttoPV60]

You have mentioned that Tesla is offering a reconditioned engine with 4years warranty. Then why the new (reconditioned) engine replaced two years ago can’t be replaced under their warranty?

The vehicle was still fully guaranteed (initial warranty of 8 years for new vehicles) when Tesla changed the engine 2 years ago. this engine replacement was therefore free of charge. But, when this happens, the parts changed free of charge are not guaranteed longer than the initial 8-year warranty period for new vehicles.

 

[dannycamps]

Might be worth a read through:

DIY Tesla Drive Unit Repair

Check the youtube channel I started about DIY repair of the Tesla Large Drive Unit (DU). This may benefit those who like to fix their car themselves, epecially if it's out of warranty. Here is the link: https://youtube.com/channel/UCIHg1trfQQTYIA88w-ZcCdw Background: The DU in my 2012 Toyota...

teslamotorsclub.com

 

[howardc64]

Here is what is involved. Deadly HV so be sure you know how to disable HV and all necessary precautious (LDU rebuild website link in my signature contains HV precaution info)

• What you are calling the engine is the LDU (Large Drive Unit) Seems to have common seal leak problem with remanufactured units.
• You could have 2 possible current leak source inside the LDU. The stator windings and inverter. Need to completely open up to fix

Here is list of what components fail inside LDU. Since your car stopped running. I'd imagine stator windings and inverter (hopefully just the harness) are suspect.

Tesla LDU - Failure Testing (google.com)

I think no way to fix without opening up LDU.

Never seen B+ B- cable failure before. Thats a new one.

Usually, coolant inside inverter housing can be confirmed by seeing coolant traces inside the B+ B- orange cover. Your cover has been off for awhile but coolant is notorious for not wanting to evaporate.

Tesla LDU - Failure Testing

Table of contents

sites.google.com

Have a couple of questions for you

• Your reman LDU only lasted 2 years. May I ask how many km?
• Can you post a pic of LDU sticker? It shows original manufacturing date, reman date, and revision level
• If you pull the speed sensor, see if there is a vent hole in that chamber. We see some LDUs don't have vent holes which would limit coolant migration. But sounds like your inverter probably have coolant which would suggest you have this vent hole. Directions to speed sensor pull here

Sign in - Google Accounts

I suspect poor seal and/or rebuild job are the causes. Tesla likely have multiple rebuild shops worldwide doing LDU reman now so I'd imagine quality control might be challenging. Coolant seal installation is quite unique from typical rubber seals, much more error prone and require good experience.

 

[OttoPV60]

Here is what is involved. Deadly HV so be sure you know how to disable HV and all necessary precautious (LDU rebuild website link in my signature contains HV precaution info)

• What you are calling the engine is the LDU (Large Drive Unit) Seems to have common seal leak problem with remanufactured units.
• You could have 2 possible current leak source inside the LDU. The stator windings and inverter. Need to completely open up to fix

Here is list of what components fail inside LDU. Since your car stopped running. I'd imagine stator windings and inverter (hopefully just the harness) are suspect.

Tesla LDU - Failure Testing (google.com)

I think no way to fix without opening up LDU.

Never seen B+ B- cable failure before. Thats a new one.

Usually, coolant inside inverter housing can be confirmed by seeing coolant traces inside the B+ B- orange cover. Your cover has been off for awhile but coolant is notorious for not wanting to evaporate.

Tesla LDU - Failure Testing

Table of contents

sites.google.com

Have a couple of questions for you

• Your reman LDU only lasted 2 years. May I ask how many km?
• Can you post a pic of LDU sticker? It shows original manufacturing date, reman date, and revision level
• If you pull the speed sensor, see if there is a vent hole in that chamber. We see some LDUs don't have vent holes which would limit coolant migration. But sounds like your inverter probably have coolant which would suggest you have this vent hole. Directions to speed sensor pull here

Sign in - Google Accounts

I suspect poor seal and/or rebuild job are the causes. Tesla likely have multiple rebuild shops worldwide doing LDU reman now so I'd imagine quality control might be challenging. Coolant seal installation is quite unique from typical rubber seals, much more error prone and require good experience.

Thank you for the feedback. I'm going back to the Tesla garage on Monday morning. I will then send you the requested information. I will check too if it was rainwater or coolant (blue). I am looking for who could repair my LDU but in Europe it seems difficult to find.

 

[Gtech]

Here is what is involved. Deadly HV so be sure you know how to disable HV and all necessary precautious (LDU rebuild website link in my signature contains HV precaution info)

• What you are calling the engine is the LDU (Large Drive Unit) Seems to have common seal leak problem with remanufactured units.
• You could have 2 possible current leak source inside the LDU. The stator windings and inverter. Need to completely open up to fix

Here is list of what components fail inside LDU. Since your car stopped running. I'd imagine stator windings and inverter (hopefully just the harness) are suspect.

Tesla LDU - Failure Testing (google.com)

I think no way to fix without opening up LDU.

Never seen B+ B- cable failure before. Thats a new one.

Usually, coolant inside inverter housing can be confirmed by seeing coolant traces inside the B+ B- orange cover. Your cover has been off for awhile but coolant is notorious for not wanting to evaporate.

Tesla LDU - Failure Testing

Table of contents

sites.google.com

Have a couple of questions for you

• Your reman LDU only lasted 2 years. May I ask how many km?
• Can you post a pic of LDU sticker? It shows original manufacturing date, reman date, and revision level
• If you pull the speed sensor, see if there is a vent hole in that chamber. We see some LDUs don't have vent holes which would limit coolant migration. But sounds like your inverter probably have coolant which would suggest you have this vent hole. Directions to speed sensor pull here

Sign in - Google Accounts

I suspect poor seal and/or rebuild job are the causes. Tesla likely have multiple rebuild shops worldwide doing LDU reman now so I'd imagine quality control might be challenging. Coolant seal installation is quite unique from typical rubber seals, much more error prone and require good experience.

I know Tesla will replace HV cables when they do a driveunit when they see evidence for moisture/oxidation.

Picture in OP isn't looking as bad like this but it's just as an example I wanted to share with you:

 

[Synthax]

In my opinion, it is not the humidity present but the degradation of insulation of components in the motor unit, that is giving you poor Megger readings. It is best not to risk short circuit and fire when the motor loaded. I think a 4 year warranty motor is a good option. It sucks but honestly this is not a DIY. Don't risk your life.

The car already has demonstrated its capability to detect a dangerous situation, if it continues to fail isolation checks it just won't start.

Thank you for your interest.

If I dry it and the megohmmeter (Megger) reads infinity after drying: that indicates that the problem was due to humidity.
Why would there be a fire hazard please ? do you think corrosion ? but I think that : if there is corrosion, the default will remain visible to the Megger and therefore the engine will have to be changed. no ?

If drying does not change the current leak: this will prove that it was not due to humidity. in this case, I will have to change the engine.

for 6 500€ I really want to try

If you get it apart with the guides others in this thread have linked and see corrosion, isopropanol, nylon brushes, and some rags are going to be a big help. Clean, clean, and clean some more, don't be afraid to make heavy use of isopropanol, it's used widely in the electronics industry to displace water, and it evaporates WAY faster than water does. Bonus: it's non-conductive and non-corrosive. After you've given it its little isopropyl sponge bath, you can stick it in a big sealed box with a bunch of desiccant to really be sure all the liquid has evaporated off. Careful not to use metal tools on sealing surfaces, and get a seal kit if you're going to be disassembling.

Edit: Oh, as an aside, while it's not like the car is just going to randomly power on with you under it and start sending high voltage to the motor, disconnect the firefighter's loop under the hood just to be safe. And disconnect the 12v system also. Really just to dot your i's and cross your t's, but you should do it anyway. Drive a bit after, and repeatedly check for leaks in the days and weeks afterward, I've heard some rumors about issues with people sealing drive units back up, but that might just be the gear box they're referring to, I don't remember exactly. Don't forget to top off the coolant, you'll lose a bit in the process.

 

[howardc64]

I know Tesla will replace HV cables when they do a driveunit when they see evidence for moisture/oxidation.

Picture in OP isn't looking as bad like this but it's just as an example I wanted to share with you:

Thanks, mine looked much better but its pretty clear there is a cavity to pool dirt or moisture and work against that o-ring. An obvious better design would be to insert the cable from bottom upwards or add a boot to wrap over cable and housing where cable inserts into.

https://teslamotorsclub.com/tmc/attachments/img_2574-1-jpeg.853054/

I probably should have cleaned off the sand that settled in the cavity on mine

 

[howardc64]

The car already has demonstrated its capability to detect a dangerous situation, if it continues to fail isolation checks it just won't start.

If you get it apart with the guides others in this thread have linked and see corrosion, isopropanol, nylon brushes, and some rags are going to be a big help. Clean, clean, and clean some more, don't be afraid to make heavy use of isopropanol, it's used widely in the electronics industry to displace water, and it evaporates WAY faster than water does. Bonus: it's non-conductive and non-corrosive. After you've given it its little isopropyl sponge bath, you can stick it in a big sealed box with a bunch of desiccant to really be sure all the liquid has evaporated off. Careful not to use metal tools on sealing surfaces, and get a seal kit if you're going to be disassembling.

ISO is good for stator clean up. These guys even spray it on haha... Might block off the gear oil seal. These guys even sprays it down with it haha

Edit: Oh, as an aside, while it's not like the car is just going to randomly power on with you under it and start sending high voltage to the motor, disconnect the firefighter's loop under the hood just to be safe. And disconnect the 12v system also. Really just to dot your i's and cross your t's, but you should do it anyway. Drive a bit after, and repeatedly check for leaks in the days and weeks afterward, I've heard some rumors about issues with people sealing drive units back up, but that might just be the gear box they're referring to, I don't remember exactly. Don't forget to top off the coolant, you'll lose a bit in the process.

My first time around HV. Have to say I paused a little before putting my non insulated sockets on the B+ B- connection haha. But yes, not rocket science safety. But anyone who is procedurally sloppy or don't follow directions well probably should be cautious. HV will kill you.

On post assembly leaks, I had to tighten the bottom 2 bolts on the coolant manifold to stop minute wetness. 4Nm wasn't enough. I heard @danielk04 try to skip RTV there since it had an o-ring but eventually had to RTV.

 

[gillmj24]

Regarding your earlier post, your previous lower estimate (pdf file here in the USA) might be in your phone's cache, or in your downloaded files section if you have an Android phone. Someone else with an iPhone can advise if apple phones keep downloads somewhere you can find them. I'm assuming you're talking about the pdf estimate that is sent to you in the phone app.

 

[OttoPV60]

Regarding your earlier post, your previous lower estimate (pdf file here in the USA) might be in your phone's cache, or in your downloaded files section if you have an Android phone. Someone else with an iPhone can advise if apple phones keep downloads somewhere you can find them. I'm assuming you're talking about the pdf estimate that is sent to you in the phone app.

Yes, I look at quotes in the Tesla app on my iPhone. I just looked in the Files app on my iPhone but there is nothing. I think you have to import them. Fortunately, I had made a screen print of the first initial total amount. I will pass the original total amount to Tesla and it is up to them to find out the détail and where their difference comes from.

 

[OttoPV60]

ISO is good for stator clean up. These guys even spray it on haha... Might block off the gear oil seal. These guys even sprays it down with it haha

My first time around HV. Have to say I paused a little before putting my non insulated sockets on the B+ B- connection haha. But yes, not rocket science safety. But anyone who is procedurally sloppy or don't follow directions well probably should be cautious. HV will kill you.

On post assembly leaks, I had to tighten the bottom 2 bolts on the coolant manifold to stop minute wetness. 4Nm wasn't enough. I heard @danielk04 try to skip RTV there since it had an o-ring but eventually had to RTV.

thank you, you found me a repairman for the LDU in Europe.
But, YouTube says it's in Ukraine. Unfortunately, this is not the right time to go there.

 

[OttoPV60]

I'm getting out of the garage right now.

The technician confirms that it was water that came out. Not coolant.
I passed a cotton swab through the B+B penetration. There is no color (blue).

I asked the tech to open the inspection hatch in the center of the LDU and contact me to let me know if it's wet.

I think I'll take the vehicle home to dry out the LDU and megger test.

There was no LDU label with the requested info. Only references.

For the 500€ more, he thinks that it is the price of the LDU which has increased in the meantime.

 

[KalJoMoS]

If you decide to go with DIY approach then here is one possible option. I believe you can find even closer options as there must be shops closer to you (NED, GER).

 

[howardc64]

thank you, you found me a repairman for the LDU in Europe.
But, YouTube says it's in Ukraine. Unfortunately, this is not the right time to go there.

Here is one in Norway

EV Services

The technician confirms that it was water that came out. Not coolant.
I passed a cotton swab through the B+B penetration. There is no color (blue).

I asked the tech to open the inspection hatch in the center of the LDU and contact me to let me know if it's wet.

I think I'll take the vehicle home to dry out the LDU and megger test.

Surprising it is water. Was the car flooded or rear tires submerged 1/2 way in water? That is the only way I can see water getting in.

Your LDU was brand new (not Re-Manufactured). Manufactured in 2019 and Rev T.

 

[OttoPV60]

Surprising it is water. Was the car flooded or rear tires submerged 1/2 way in water? That is the only way I can see water getting in.

I'm also surprised that water is able to fit inside. Just by the joints of the HV cables?
No, there was no flooding or submersion. There is just the current winter rain here.

There is a slight corrosion on each side of my O-rings. Not big.
Not as big as the Gtech example (in post #9)

 

[OttoPV60]

I enclose the invoice for the replacement of the HV cables.

The technician opened the inspection hatch in the middle: it's dry.
The technician says that the water may not have reached the middle.

I'm bringing the vehicle home tomorrow.