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DC - DC converter / AC compressor repair

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That thread looks good, ill have to check it out.
as far as tips and tricks go
************This is super easy, yes you can do it yourself, minimal tools required************************

Let me break down the process.
-Disconnect power. 12v and high power
-Remove passanger front wheel
-remove wheel well liner, its attached by 3 or 4 plastic clips. Doesnt need to be completley out, just out of the way.
-In plain view for the world to see is the fully accessible DC-DC converter.
-Two clamps from my woodworking area, one to each coolant hose.
-disconnect coolant hoses, you can do it at the hose clamp and remove the hose or the whole fitting is attached with 4 screws on each one, thats what I did is take the screws out, it was easier than discnnecting the hose as it was being difficult.
-Next remove all 4 connectors, and then remove the grounding wires by taking the nuts off the wire.
-Remove the black clips around the edges which help route other wiring.
- The DC-DC converter is attached to the body of the car with 2nuts and one bolt, once those are removed the whole thing comes out, its a little difficult as the mounting is akward, youll know when you see it what Im talking about but if you wiggle it a bit you will get it off. (I used a drill to bore out the mounting location on the DC-DC converter itself it didnt affect anything and really helped when putting it back in.)


-The hardest part is this, separating the converter, the gasket is sealed well,Remove the 6 screws around the outside of the housing then start on the gasket. Im sure there are lots of ways to do it but I used a hammer, razor blade and a screw driver to separate the two pieces, being careful to not drive the screw driver inside but only around the edges so that it would make a gap big enough to get my razor in to cut the gasket. DO this all the way around.
-after its separated the hard part is over, there are a total of 4 fuses, check them all with your meter, replace what is bad. (with an identical fuse)
- Now clean off the rest of the old gasket and replace with a liquid gasket from the autoparts store, this is very important so that you dont get water in here and develop a real problem later on.
-Seal it up and put it back in.
-turn heat/AC on and enjoy :) .

PS if you break the plastic clips on the tire area you can replace them from ebay, I dont know why but they are priced like gold at autozone and you can get 100 for a like 2$ on ebay.
-using the razor blade clean off the old gasket and


Tips?
DO NOT REMOVE THE HEATER. I did and it just costed alot of time, added nothing to the whole process, I had to reinstall the heater just to check it so you know, I should have just started with the DC-DC and been good
Tricks?
Dont be scared its super easy and itll save you a ton of money.
Excellent.. thanks for laying this out... will be helpful if/when I ever face this.

(also, in that charger replacement thread I referenced, the youtube video from Nick S is very helpful)
 
Yes.
My thought was a small housing on the unit that had 4 screws on nuts, whatever. THe plastic of the housing would be Bright orange like the other HV coloring and a warning on the plastic. once the screws are removed the plastic can be removed and there are 2 large fuses that can be removed and replaced.

I get you, that's like the pack pyro fuse, I think. I'm guessing they didn't expect to need to change the fuse. If they PWM the PTC, it might even be a SW issue that caused the failure (lack of soft start).
 
Sledom, Could I recommend that, since you put together a simple list, that you edit it to add a note that a person should have some PPE and understanding that they are exposing themselves to 400V DC when they uncover the HV cables during disassembly from the car? While the list sounds like it's just like changing out a fuse in a ICE car, the level of risk here is significant (Death) if not done correctly. -Peter
 
Sledom, Could I recommend that, since you put together a simple list, that you edit it to add a note that a person should have some PPE and understanding that they are exposing themselves to 400V DC when they uncover the HV cables during disassembly from the car? While the list sounds like it's just like changing out a fuse in a ICE car, the level of risk here is significant (Death) if not done correctly. -Peter
***THIS***
on it
 
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These fuses are designed to be replaceable in cars with the 2nd generation DC-DC converter, which was introduced in approximately January 2014.

In the 1st generation DC-DC that @sledom shows in post #27, the forward junction box (FJB) high voltage distribution functions are inside the DC-DC converter. In the newer design, the DC-DC converter and forward junction box are separate. The fuses are inside the forward junction box in this design and more easily accessible than the older cars.

The fuses were absolutely designed to be replaced in the later cars--I wrote and edited the replacement instructions when I worked for Tesla. I think the technician mentioned earlier in the thread had it backwards.


is there a guide somewhere on how to access the dc to dc converter, open it up, and check / replace the fuses?

Yes, A/C compressor, PTC (cabin) heater, and battery coolant heater fuse replacement procedures are in the Service Manual for cars with the separate forward junction box (cars built after roughly January 2014). If I remember correctly, the procedures are titled by the size of the fuse, something like "Fuse - HV - FJB - 40 Amp".

It may not be common knowledge yet, but the service.teslamotors.com site is now available to anyone in the U.S. (though you still have to pay for a subscription). It was formerly only available to residents of Massachusetts.
 
These fuses are designed to be replaceable in cars with the 2nd generation DC-DC converter, which was introduced in approximately January 2014.

In the 1st generation DC-DC that @sledom shows in post #27, the forward junction box (FJB) high voltage distribution functions are inside the DC-DC converter. In the newer design, the DC-DC converter and forward junction box are separate. The fuses are inside the forward junction box in this design and more easily accessible than the older cars.

The fuses were absolutely designed to be replaced in the later cars--I wrote and edited the replacement instructions when I worked for Tesla. I think the technician mentioned earlier in the thread had it backwards.




Yes, A/C compressor, PTC (cabin) heater, and battery coolant heater fuse replacement procedures are in the Service Manual for cars with the separate forward junction box (cars built after roughly January 2014). If I remember correctly, the procedures are titled by the size of the fuse, something like "Fuse - HV - FJB - 40 Amp".

It may not be common knowledge yet, but the service.teslamotors.com site is now available to anyone in the U.S. (though you still have to pay for a subscription). It was formerly only available to residents of Massachusetts.

Wow thats good info, looks like your new here, WELCOME!(not many messages)
From what I understand the 2nd gen is in a different place so swapping out 1st gen for second gen is not possible. I am glad to hear that the fuses are more accessible.
 
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Hi all,

I know that it has been some time now since this discussion, but this issue has come around to bother me as well.

Just eight months after my warranty expired on my Model S P85 the A/C stopped cooling after my 12V battery got replaced in January this year.

I got today the verdict that the DC/DC converter would cost me 3500 euro plus labor and diagnostics.

Trying to escalate this to the lead service center manager here in Austria, I hope that they recognize that our 1st Gen DC/DC converters have design flaw and they offer to fix this at no cost. Need to replace the whole part just because most probably one or two fuses have blown.

Will keep you posted, while I wanted to share with you this site that I found today about all parts for our cars (link to the DC/DC converter):

https://epc.teslamotors.com/?_ga=2....6950-622216554.1535637908#/systemGroups/53947

You can go back a check any part and its' number.

Have nice weekend.
 
IT WORKS!

I have followed this subject and this thread (and many like it) very closely. The heat in my 2013 did not work. Tesla wanted $3,500 to do the repair. This was all completely sight-unseen. After reading through this thread, I called the local Service Center and told them that there was a strong possibility that the culprit was a $16 fuse and begged them to simply change the fuse in the DC-DC converter. I told them if this was not the problem, that I'd agree to pay them to do the fuller repair. They refused to budge. They wanted to do the entire repair or nothing at all. I was on the phone with the guy for more than a half hour. Wouldn't budge an inch.

So ... I decided to go it alone. I got a hold of two fuses (courtesy of one of the members of this forum!) and armed with nothing more than the instructions of Post #59 of this thread, written by @sledom, I found a mechanic who was willing to gut it out with me. We pulled out the DC-DC converter and after opening it up (not a fun task!), we ran a meter on the existing fuses in there and saw that one of them was completely dead. I knew instantly that this was the culprit and that once I replaced it, I would have heat flowing again. Realizing that if one of them was dead, the other was sure to follow soon, we popped both of them out and replaced them with the new ones. We put the converter back in place, hooked everything back up again, and with fingers crossed, fired up the heat and it worked beautifully!

I am SO grateful for the collective wisdom in this forum and for the passionate Tesla owners who love sharing their knowledge. @sledom answered all my questions and stayed in constant contact with me, even as the repair was happening! I hope the information here is helpful to someone else, and if it saves you any amount of money (in my case, thousands!), then that's a win for all of us!
 
Only 1 fuse was bad
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@rsg123, my understanding is that after Tesla realized they had a problem with blown fuses in the nearly impossible to reach first gen DC-DC units, they corrected that by making the fuses far more accessible in each succeeding generation.

Total BS. takes about 2 hours to raise the car, remove the tire and inner fender. disconnect the HV cables, remove the converter, find the blown fuse, replace and put everything back together.
 
@Gixx1300R, you're right. Getting to the unit itself isn't rocket science. You certainly have to be careful because of the high voltage stuff, (I found the Tesla mechanical manual to be quite helpful with that). But the real pain in the butt is getting INTO the unit itself. It's quite cumbersome and requires a lot of patience. The silicone gasket in the unit is really tough to penetrate and break open. At least it was for us. Just want to make sure people have the right expectation. Bottom line: This is totally doable, and you don't have to pay Tesla thousands of dollars to do this repair!
 
Hi all,

I have planned my fuse replacement exercise for mid June as I am on the road a bit until then and also getting my buddy to join me for moral and electrical support. :)
Driving the car should not be an issue until then right?

Two questions:
@Gixx1300R, how did you get the A/C coolant hoses plugged to avoid spill/leakage of the fluid?
Also, can you share the link to the "Tesla mechanical manual for the voltage stuff".

I have this one, just want to make sure that I have the right one:
https://rts.i-car.com/images/pdf/oem-info/tesla/body-repair-tech-notes/28634.pdf

Thanks.
 
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@alexbdim, if you have a first-gen car, then you should be fine with the instructions on pages 18-20 on that PDF. As far as the coolant hoses, you just need to clamp them before removing them. Have a small bucket nearby to catch excess fluids that may leak out. Pretty simple process. If you want more detailed step-by-step instructions on this, private message me and I'll shoot them over to you.
 
@Gixx1300R, you're right. Getting to the unit itself isn't rocket science. You certainly have to be careful because of the high voltage stuff, (I found the Tesla mechanical manual to be quite helpful with that). But the real pain in the butt is getting INTO the unit itself. It's quite cumbersome and requires a lot of patience. The silicone gasket in the unit is really tough to penetrate and break open. At least it was for us. Just want to make sure people have the right expectation. Bottom line: This is totally doable, and you don't have to pay Tesla thousands of dollars to do this repair!

There is a technique that I used to get into it that took about 20 minutes. Use a razor knife around the edges to cut the adhesive. Tap the back of the razor knife as it moves along the edge
 
Hi all,

I have planned my fuse replacement exercise for mid June as I am on the road a bit until then and also getting my buddy to join me for moral and electrical support. :)
Driving the car should not be an issue until then right?

Two questions:
@Gixx1300R, how did you get the A/C coolant hoses plugged to avoid spill/leakage of the fluid?
Also, can you share the link to the "Tesla mechanical manual for the voltage stuff".

I have this one, just want to make sure that I have the right one:
https://rts.i-car.com/images/pdf/oem-info/tesla/body-repair-tech-notes/28634.pdf

Thanks.

I used a pair of hemostat clamps