PTC cabin heater repair

Hello,

I have 2017 Model X. About a week ago I smelled burning electronics inside the cabin and almost immediately after that heard a fuse pop. Then it was only cool air coming out of the vents. I knew it was the heater.

I took the PTC heater off and took it apart. There are 6 IGBT-modules controlling the actual heater elements. Heater itself consists of 9 different heating elements. They are controlled as follows; 3 elements have individual IGBT and 6 other elements are paired to one IGBT per two elements. I guess they are shuffled and they are not fully on all the time.

I measured resistance between those 9 elements. Measurements were between 1000 and 1500 ohms. Broken element had more than 33 000 ohm resistance. Also its controlling IGBT was shorted (drain to source). I desoldered the element from control board before measuring. It is relatively easy to measure resistance even if element is still attached to control board.

I desoldered all the IGBTs from control circuit and replaced all but shorted one with new ones. Put the whole element back in the car and replaced hv-fuse in front high voltage junction box. Heater came back alive and did not blow fuse again. One out of nine elements is not providing me heat but it is way better than driving without heat at all. Here in Finland its below zero celcius right now so heat is more than welcome.

Ranger quoted me 1300€+ for replacing the elements + fuse. Replacement IGBTs were 70€ including shipping fees. Replacement fuse was about 50€ from Tesla. I could have sourced it for about 10€ but I was in hurry to get it.

I will post some pictures with explanations soon.

 

[brainhouston]

The actual PTC element is just a passive component. It is like multiple big resistors in one package. One of those "resistors" traces is broken inside the element in my case. You (or your electrician) can measure it with multimeter and see which one has too much resistance.

I think if the logic board is damaged even new IGBTs can blow right away if not driven properly. One should always measure all the other IGBTs and look for potential short circuit before putting it back in with new fuse.

Too much or too little (aka short)

 

[Cris disrupts]

You try Full SW reinstall? maybe the replacement PTC unit is defective.

After the full reinstall of the software I still dont see any improvement. These 3 errors are still present. This one worries me the most: THC_w0183_PTCCanTmo

BARD's description of the errors:
-----------------------------
THC_w0183_PTCCanTmo
-----------------------------
The error code THC_w0183_PTCCanTmo indicates a problem with the PTC (Positive Temperature Coefficient) sensor. The PTC sensor is a type of thermistor that measures temperature. It is used in the Tesla Model X to monitor the temperature of the battery pack.
The error code THC_w0183_PTCCanTmo means that the PTC sensor is not communicating properly with the vehicle's battery management system (BMS). This could be due to a problem with the sensor itself, or with the wiring between the sensor and the BMS.

If you see this error code, you should take your vehicle to a Tesla service center to have it checked out.

In the meantime, you can still drive your vehicle, but you should be aware that the battery pack may not be operating at optimal efficiency. You may also experience reduced range or performance.
Here are some additional details about the error code:

• THC: This code indicates that the problem is with the battery pack.
• w0183: This code is a specific code for the PTC sensor.
• PTCCanTmo: This code means that the PTC sensor is not communicating with the BMS.

-----------------------------
THC_d0022_RCCMSensor
-----------------------------
The error code THC_d0022_RCCMSensor indicates a problem with the RCCM (Remote Charging Control Module) sensor. The RCCM sensor is a type of current sensor that measures the amount of current flowing into or out of the battery pack. It is used in the Tesla Model X to monitor the charging and discharging process of the battery pack.

The error code THC_d0022_RCCMSensor means that the RCCM sensor is not communicating properly with the vehicle's battery management system (BMS). This could be due to a problem with the sensor itself, or with the wiring between the sensor and the BMS.

-----------------------------
THC_w0209_RCCMRightFloorDuctSns [this may be caused by me because i did not install the glovebox and all the parts inside the right front cabin AFTER i installed the PTC Heater from eBay]
-----------------------------
The error code THC_w0209_RCCMRightFloorDuctSns indicates a problem with the Right Floor Duct Sensor (RCCM). The RCCM is a sensor that measures the temperature of the air flowing through the right floor duct. It is used to control the operation of the climate control system.

The error code THC_w0209_RCCMRightFloorDuctSns means that the RCCM is not communicating properly with the vehicle's body control module (BCM). This could be due to a problem with the sensor itself, or with the wiring between the sensor and the BCM.

 

[Cris disrupts]

Did you checked the 12V fuse for PTC heater?

yes, i checked all the RED 10A fuses from the front trunk box:

F112	MICRO2 5A	Cabin Climate Controls, Front / Ionizer
F113	MICRO2 10A	Cabin Heater, Rear Climate Control, Air Quality Sensor
F114	MICRO2 10A	Termal Controller, Battery Heater, Inlet, Chiller Valve

Should I check also the interior Fuse Box? i see the BMS one is inside...

Fuse Box Diagram Tesla Model X (2015-2018)

Fuse box diagrams (location and assignment of electrical fuses and relays) Tesla Model X (2015, 2016, 2017, 2018).

fuse-box.info

 

[Gtech]

yes, i checked all the RED 10A fuses from the front trunk box:

F112	MICRO2 5A	Cabin Climate Controls, Front / Ionizer
F113	MICRO2 10A	Cabin Heater, Rear Climate Control, Air Quality Sensor
F114	MICRO2 10A	Termal Controller, Battery Heater, Inlet, Chiller Valve

View attachment 989470


Should I check also the interior Fuse Box? i see the BMS one is inside...

Fuse Box Diagram Tesla Model X (2015-2018)

Fuse box diagrams (location and assignment of electrical fuses and relays) Tesla Model X (2015, 2016, 2017, 2018).

fuse-box.info

I would measure on the small connector of the PTC directly since there are some connections between fuse F113 and PTC

I suggest if PTC gets 12V and proper ground it must give can signals so then maybe PTC is dead or can is down. I see it is on same CAN as RCCM so that's interesting

 

[MP3Mike]

[this may be caused by me because i did not install the glovebox and all the parts inside the right front cabin AFTER i installed the PTC Heater from eBay]

It is possible that this is your problem. Depending on the CAN wiring, if it passes through there, or a terminator is in the part you didn't reinstall.

 

[Cris disrupts]

It is possible that this is your problem. Depending on the CAN wiring, if it passes through there, or a terminator is in the part you didn't reinstall.

The air duct behind glovebox was installed and sensor was connected ...also the glovebox.

1 error less, but the first 2 are still there:

Ran a thermal test after:

 

[Cris disrupts]

Latest update: Heat is flowing again from my original 2017 heater. Thank you all for your support.
It seems that the heating element behind the IGBT1 was the cause for my problems. I decided to cut and remove the IGBT1 because of the readings I saw on my multimeter:

Multimeter displayed 1 between positive(red wire) and heating element #1, this means no continuity (i guess):

Multimeter displayed 1672 between positive(red wire) and heating element #3, similar values (or around 50%) were displayed for the other 7 heating elements.

Quick fix to swap the PTC for Tesla Model X, if you do not need to replace the 40A fuse: I took out the red and black wires from the original PTC and I swap the heater from the car with the original one (IGBT1 cut out) without needing to uninstall the entire frunk in order to take out the PTC connector from the DC-DC convertor/fuse box.

Put all the components back in the car and connected all the wires + safety loop.

Started the MCU and entered service mode, it does not like the ptc Version Mismatch (the heater from eBay was from 2016, the original one is from 2017) :

Decided to do a FULL Software reinstall and run a thermal test. All good now!

This is the fuse I have installed (instead of the original SIBA 40A 690/700V 200kA):
EATON BUSSMANN 40A 120kA 14x51mm,

 

[brainhouston]

nice work!
can u clarify, if u put ur original, how did u get ver mismatch?

 

[Cris disrupts]

nice work!
can u clarify, if u put ur original, how did u get ver mismatch?

The one from ebay(2016, orange connector) was on the car before I installed the original (2017, white connector) one

 

[Retkimora]

I see it is on same CAN as RCCM so that's interesting

This is interesting. I am having intermittent charging problems like EVSE not recognizing car or car telling me CP signal is not present. Charging always starts but it might take 0-45 minutes for car to get that CP signal. After that it charges just fine. This is a bit off-topic but maybe once broken PTC is giving can network hard time. There is also some CanMCUtmo -message around at the same time. It disappears when everything works nice.

 

[Pasi Pelli]

Hello,

I have 2017 Model X. About a week ago I smelled burning electronics inside the cabin and almost immediately after that heard a fuse pop. Then it was only cool air coming out of the vents. I knew it was the heater.

I took the PTC heater off and took it apart. There are 6 IGBT-modules controlling the actual heater elements. Heater itself consists of 9 different heating elements. They are controlled as follows; 3 elements have individual IGBT and 6 other elements are paired to one IGBT per two elements. I guess they are shuffled and they are not fully on all the time.

I measured resistance between those 9 elements. Measurements were between 1000 and 1500 ohms. Broken element had more than 33 000 ohm resistance. Also its controlling IGBT was shorted (drain to source). I desoldered the element from control board before measuring. It is relatively easy to measure resistance even if element is still attached to control board.

I desoldered all the IGBTs from control circuit and replaced all but shorted one with new ones. Put the whole element back in the car and replaced hv-fuse in front high voltage junction box. Heater came back alive and did not blow fuse again. One out of nine elements is not providing me heat but it is way better than driving without heat at all. Here in Finland its below zero celcius right now so heat is more than welcome.

Ranger quoted me 1300€+ for replacing the elements + fuse. Replacement IGBTs were 70€ including shipping fees. Replacement fuse was about 50€ from Tesla. I could have sourced it for about 10€ but I was in hurry to get it.

I will post some pictures with explanations soon.

Hi Retkimora

It seems we live in the same town in Finland so I could write in Finnish but let's keep in English . Since one year ago you had this problem, is it still working after repair?

I do not have problems yet with my model s 2015 but I have understood that the cabin heater problem is quite common, so I am going to buy one in case I will need it in the future. Because I need my car daily I do not have time to wait to get car on the road again.

One solution is to buy ptc from eBay, It costs only about 150e or to buy 9 igbts (and the fuse) waiting for the day PTC get broken. I think the first solution is the fastest when the problem occurs.

 

[Retkimora]

Hello. Good to see fellow Finnish people here. I have read a used part with different logic board might not work right away. Maybe full software reinstall gets new part working? This is something to research before the original heater gives up.

 

[JSD17]

The issue is the lack of heating, the original PTC heater stopped working this spring. 40A fuse was also blown

I purchased an used PTC heater from eBay(from US, delivered to Romania in July) and last week I decided to install it, together with a new 40A 14x51mm fuse.

Now the PTC heater is green, but i still do not get any heat:
View attachment 989013

From Service mode I ran a Thermal Test and I get this:
View attachment 989014

Active errors now:
View attachment 989015

The model number (1060432-00-A) of the heater purchased from eBay(installed on the car now):
View attachment 989016

The model number (1060432-00-C) of the original heater(removed from the car):
View attachment 989020

The good part is that I now manage to change the heater and 40A fuse in less than 90minutes...i did this task 4 times in the past week.

Any help and suggestion would be highly appreciated!

How are you able to run the thermal tests by yourself?

I got a 2012 Model S. I get heating one side (drivers side) and nothing on the passengers side. Drivers side cycles between cold and hot sometimes also. Took it to Tesla to diagnose, they said failing PTC heater. I replaced the PTC heater elsewhere after buying a 'new' one on eBay - the same issue persists.

Tesla refuses to acknowledge they could have misdiagnosed and refuses to proceed without having me buy and install the PTC through them. I don't think the PTC is the issue as both PTC heaters blow air on the drivers side only. I'm not sure how to proceed here. Is there anyway I can run thermal tests or narrow down the issue?

The front passengers side actuator was also showing a fault and I replaced that through Tesla and that fault is no longer showing but it did not correct the issue.

 

[Konst74]

Latest update: Heat is flowing again from my original 2017 heater. Thank you all for your support.
It seems that the heating element behind the IGBT1 was the cause for my problems. I decided to cut and remove the IGBT1 because of the readings I saw on my multimeter:

Multimeter displayed 1 between positive(red wire) and heating element #1, this means no continuity (i guess):
View attachment 989788

Multimeter displayed 1672 between positive(red wire) and heating element #3, similar values (or around 50%) were displayed for the other 7 heating elements.
View attachment 989789


Quick fix to swap the PTC for Tesla Model X, if you do not need to replace the 40A fuse: I took out the red and black wires from the original PTC and I swap the heater from the car with the original one (IGBT1 cut out) without needing to uninstall the entire frunk in order to take out the PTC connector from the DC-DC convertor/fuse box.

Put all the components back in the car and connected all the wires + safety loop.

Started the MCU and entered service mode, it does not like the ptc Version Mismatch (the heater from eBay was from 2016, the original one is from 2017) :
View attachment 989797

Decided to do a FULL Software reinstall and run a thermal test. All good now!
View attachment 989798

View attachment 989800

This is the fuse I have installed (instead of the original SIBA 40A 690/700V 200kA):
EATON BUSSMANN 40A 120kA 14x51mm,
View attachment 989802

Latest update: Heat is flowing again from my original 2017 heater. Thank you all for your support.
It seems that the heating element behind the IGBT1 was the cause for my problems. I decided to cut and remove the IGBT1 because of the readings I saw on my multimeter:

Multimeter displayed 1 between positive(red wire) and heating element #1, this means no continuity (i guess):
View attachment 989788

Multimeter displayed 1672 between positive(red wire) and heating element #3, similar values (or around 50%) were displayed for the other 7 heating elements.
View attachment 989789


Quick fix to swap the PTC for Tesla Model X, if you do not need to replace the 40A fuse: I took out the red and black wires from the original PTC and I swap the heater from the car with the original one (IGBT1 cut out) without needing to uninstall the entire frunk in order to take out the PTC connector from the DC-DC convertor/fuse box.

Put all the components back in the car and connected all the wires + safety loop.

Started the MCU and entered service mode, it does not like the ptc Version Mismatch (the heater from eBay was from 2016, the original one is from 2017) :
View attachment 989797

Decided to do a FULL Software reinstall and run a thermal test. All good now!
View attachment 989798

View attachment 989800

This is the fuse I have installed (instead of the original SIBA 40A 690/700V 200kA):
EATON BUSSMANN 40A 120kA 14x51mm,
View attachment 989802

Hello Cris

I have September 2017 Model X too. The same problem - I have heard a pop sound. Then it was only cool air coming out of the vents.​

At first I have replaced the 40A heater fuse in DC - DC Converter. It was shorted. I tested it by multimeter.

Then I took the PTC heater off and took it apart.

I measured resistance between those 9 elements. The one controlling IGBT №1 was shorted. I desoldered the element from control board. The resistance of all 9 elements was norm and all elements were looked undamaged. But the heater didn't work. Should I place the new IGBT on control board ?

Why did you desolder all the IGBTs from control circuit and replaced all but shorted one with new ones if they was not shorted ?

What should I do now to make the heater alive ?

 

[rcho8]

the fuse could have been blown also, did you replace the fuse?

 

[Retkimora]

Did you replace the fuse located in front HV junction box? The box itself is not dc-dc converter. There are two similar fuses inside the box. Broken fuse should measure as open-circuit, infinite ohms.

 

[rcho8]

when I replace my ptc heater, I have to replace the 40a fuse also in the front behind the air tank.

 

[subbuhere]

I hit the same issue with my Model X 2016. Took it in for diagnosis, after charging me about $300, the SC came back with another estimate of $1600 for replacing the PTC Heater and Fuse.

I'm thinking of going down the DIY route - any videos/photos/instructions that can help a first timer change the PTC Heater Core and the fuse? I saw link to a youtube video but that's more like a slideshow and not of someone actually doing it. Any help/pointers are appreciated.

Or if anyone from Seattle here, suggestions for a Seattle area shop that can do this for somewhat lesser price tag? Or any Seattle area Tesla DIY experts who can chip in to help me out here? TIA!

 

[subbuhere]

The good part is that I now manage to change the heater and 40A fuse in less than 90minutes...i did this task 4 times in the past week.

Any help and suggestion would be highly appreciated!

Wow...that's awesome you can do it in 90 min. Tesla wants to charge me 5Hrs worth of labor for swapping out the heater core and replace the fuse. Do you happen to have a video of the process for the fuse and the heater replacement? I'd really appreciate it. TIA!

 

[Retkimora]

Getting heater core out is like 30min job. Rest will be cursing in the frunk trying to reach fuse box or lifting the car up and trying to access it from below. Just disconnect hv-loop and 12V first and start disassembling everything.