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Diagnostics and repair

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I have a 2017 MS. I am working on it myself. I have a PTC Heater problem. It will not communicate with the CAN. I purchased the subscription to toolbox from tesla, but they are not helpful at all. I have the network cable and have connected it to the jack under the MCU. I have changed the ip address as listed in the knowledgebase from tesla. The program will not connect to my car through that cable. I have a cable ordered up that hopefully will connect to the can jack-db9-peak can tool-usb laptop. Is this the way it is supposed to connect? The knowledgebase also said something about the network connection under the mcu needed to be unlocked remotely.

As for the PTC Heater, I replaced the heater with another one and it has the same error. I am not great at diagnostics, which is why I am trying to use toolbox. What could cause the error on the heater? It is starting to get cold out and I would love to use more than just the seat heaters to get warm. I have called tesla who referred me to my service center. They said they do not provide any tech support. As most things with Tesla, if they don't do it, they don't want to see or hear from you. I love my car, but really wish Tesla treated me like BMW does. At least when they screw you, they kiss you and thank you while doing it.
 
I did not figure this out. I have purchased a peak can reader and various wires to go with that, but still nothing. I called several tesla 800 numbers. They all claimed to not be able to help me and sent me to the service center. I have communicated with them via email and text several times and all I get from them is "the network cable connection under the MCU does nothing". I ask how they connect at the service center, and they do not tell me. They inform me that it is proprietary and they cannot divulge this information. The only thing I can gleam from this experience is that Tesla is knowingly selling access to software they know you cannot use. I am not saying this is criminal, but I kinda am. It is such a shame that a company can make you love the car, but hate the company so much. I am seconds away from selling this car and buying any other electric on the planet. Even the pig ugly Mach-E. I know Ford has learned that the only way you get repeat customers is to provide them a service or product they both like, and can use in the future. We are only a few years away from having millions of Tesla's that they will not want to service any longer. It is going to be eye opening when all of these customers decide they should be able to work on their cars and can't because the company thinks a Linux box with wheels is a trade secret and they don't care that you purchased it for six figures. It is time to throw away your car and get a new one. By then, there will be enough selection that nobody will want it.

Sorry for the rant, but it is getting old being told we will not help you with your car and we don't want you doing anything with your car. Post up if you figure it out, because I am getting near the end of my rope with this.
 
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I may be wrong, but I think you're moving in the wrong direction. I have observed canbus through the under cubby main connector, no toolbox app needed. My homemade harness, along with Picoscope, wiring diagrams, connector location diagrams and a laptop computer should get you on the road to satisfying diagnostics. My canbus work has been preemptive, for learning and observation. My car refuses to break down.
As for training, go to Youtube and search for South Main Auto can bus. Eric O. does a great job of laying out can bus troubleshooting.
Let us know how you do
Can Cable.jpg
 
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Yes, I agree that Tesla as a company does some very questionable things. I have some access to the car through the Ethernet cable, but I cannot read any dtc’s, and I get error codes going through almost all of the actions. I am not sure why.
 
I may be wrong, but I think you're moving in the wrong direction. I have observed canbus through the under cubby main connector, no toolbox app needed. My homemade harness, along with Picoscope, wiring diagrams, connector location diagrams and a laptop computer should get you on the road to satisfying diagnostics. My canbus work has been preemptive, for learning and observation. My car refuses to break down.
As for training, go to Youtube and search for South Main Auto can bus. Eric O. does a great job of laying out can bus troubleshooting.
Let us know how you doView attachment 723219
I will definitely start there. It seems that we should not have to reinvent the wheel to diagnose and work on our cars.
 
May be a long shot but have you tried reaching out to the Electrified Garage? They may be able to point you in the right direction.
I have reached out and they are not able to do diagnostics remotely at this time. There are a few places here in Oregon who also do electric cars and they are too busy to take it in. I may have someone who is willing to at least look at it next week. I still would like to figure out all the connection stuff as I believe there will be a time when we will need to repair these ourselves. Ask any gen1 roadster owner if they feel this is necessary. The "techs" at the service center are only taught the most recent updates to the cars. The old stuff is not something they care about.
 
Very possible the PTC blew the fuse in the DC-DC converter. Have you verified your new PTC is getting any power?
Both of the fuses were replaced as that is the first thing all the forums suggested. Both fuses were good. One of the techs at the service center was nice enough to tell me they thought they would replace the ptc heater next to see if that fixed it. So I did that and the same error occurs. Fuses were not too difficult, nor was the ptc heater. Fuses just require resealing the box when you are done.
 
Isn’t it so that Tesla uses ethernet cable for the diagnoses, reachable behind that small side panel left of the dash, under IC. It’s the side of the dash that’s hidden if door is closed. I’m not an expert but have read about this in the past...
On the model s of my year, there are two places to connect that I have seen. The autopilot module above the glove box has a 4 pin wire going to it. You unplug it and connect your network cable to that. This is the port that should unlock the other port, which is beneath the MCU and above the small cubby at the center console. The model 3 has the port on the drivers side by the dead pedal. At least this is what I have found thus far.
 
Both of the fuses were replaced as that is the first thing all the forums suggested. Both fuses were good. One of the techs at the service center was nice enough to tell me they thought they would replace the ptc heater next to see if that fixed it. So I did that and the same error occurs. Fuses were not too difficult, nor was the ptc heater. Fuses just require resealing the box when you are done.
I found the PTC heater problem was the DC/DC converter was the problem with my cabin heater not working. Got one off of eBay and solved the problem. The earlier model S has the DC/DC converter located behind the passenger front wheel. CAUTION: you need to disconnect the high voltage connection by the 12v battery first!
 
I have a 2017 MS. I am working on it myself. I have a PTC Heater problem. It will not communicate with the CAN. I purchased the subscription to toolbox from tesla, but they are not helpful at all. I have the network cable and have connected it to the jack under the MCU. I have changed the ip address as listed in the knowledgebase from tesla. The program will not connect to my car through that cable. I have a cable ordered up that hopefully will connect to the can jack-db9-peak can tool-usb laptop. Is this the way it is supposed to connect? The knowledgebase also said something about the network connection under the mcu needed to be unlocked remotely.

As for the PTC Heater, I replaced the heater with another one and it has the same error. I am not great at diagnostics, which is why I am trying to use toolbox. What could cause the error on the heater? It is starting to get cold out and I would love to use more than just the seat heaters to get warm. I have called tesla who referred me to my service center. They said they do not provide any tech support. As most things with Tesla, if they don't do it, they don't want to see or hear from you. I love my car, but really wish Tesla treated me like BMW does. At least when they screw you, they kiss you and thank you while doing it.
Both of the fuses were replaced as that is the first thing all the forums suggested. Both fuses were good. One of the techs at the service center was nice enough to tell me they thought they would replace the ptc heater next to see if that fixed it. So I did that and the same error occurs. Fuses were not too difficult, nor was the ptc heater. Fuses just require resealing the box when you are done.
I found the PTC heater problem was the DC/DC converter with my cabin heater not working. Got one off of eBay and solved the problem. The earlier model S has the DC/DC converter located behind the passenger front wheel. CAUTION: you need to disconnect the high voltage connection by the 12v battery first!