THC_d0013 Coolant heater problem detected
- Thread starter dogger23
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dogger23
Member
I searched up the error one of the results here mentioned low 12 v battery voltage, but mine shows 14V.
Take a look
Note.
DC-DC converter assembly enclosure and supplies high voltage from the electric vehicle battery assembly to the
compressor assembly with bracket, battery coolant heater (uses 20A fuse, the bottom one in this photo*) and No.1 heater with bracket sub-assembly.
The DC-DC converter assembly controls the power source to the battery coolant heater using a signal from the thermal control ECU.
*
https://alflash.com.ua/2019/to_rav4ev/fuses.jpg
Note.
DC-DC converter assembly enclosure and supplies high voltage from the electric vehicle battery assembly to the
compressor assembly with bracket, battery coolant heater (uses 20A fuse, the bottom one in this photo*) and No.1 heater with bracket sub-assembly.
The DC-DC converter assembly controls the power source to the battery coolant heater using a signal from the thermal control ECU.
https://alflash.com.ua/2019/to_rav4ev/d0013.jpg
*
https://alflash.com.ua/2019/to_rav4ev/fuses.jpg
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[Remove the HV Service Disconnect from under the passenger seat before doing anything below.]
Hmmm. I don't have any experience with this system. Several Tesla Model S folks who have experienced THC_d0013 have replaced their battery heaters and not solved this issue. The battery heater is one of the early HV subsystems that is not included in the HVIL* -- a safety feature -- so be very careful if you unplug it. It's supplied HV power from the DC-DC Converter, and its plug is readily accessible there, right up top. You can test the heater for correct internal resistance ranges.
From the Service Manual, section Engine-Hybrid System, Cooling, HV_Battery Coolant Heater
That will give you a rough idea if the heater's close to being functional, but it doesn't test for HV isolation, and THC_d0013 covers a lot of different scenarios. But I wouldn't be surprised if it passes that crude test.
I think I'd check the heater against that chart of values first, then probe the output of the DC-DC Converter for an open fuse. That requires knowing a baseline resistance value of that circuit inside the DC-DC -- which I don't have ATM -- and definitely remove the HV Service Disconnect from under the passenger seat, because the system can activate the DC-DC at any time. Never probe any DC-DC HV connections unless the Service Disconnect has been removed.
If you want a baseline fuse check resistance, maybe Vlad has it (or it's somewhere in the Service Manual, and I just haven't found it). If not, I can get it from one of my RAV4 EVs in a day or two.
From what I see, aside from damaged wiring, the heater itself can cause that DTC, a failed fuse inside the DC-DC, or the DC-DC itself. That's on the HV side of things.
On the LV/sensor side . . .
. . . there are other things to check out. I lack the time right now to look into this deeper . . .
* = This is not strictly true: the mating plug on the battery heater harness does have an HVIL loopback, so unplugging it ought to open the HVIL and prevent HV contactor closure. What I meant is that the HVIL does not extend all the way to the individual components: battery heater, AC compressor, and cabin heater. But their harness KET connectors at the DC-DC do include HVIL loopbacks . If you're interested in learning more about this, see the excellent Tesla Service Bulletin SB-10052460-6095 / TN-13-44-001 "Tech Note: Troubleshooting Isolation Faults".
Hmmm. I don't have any experience with this system. Several Tesla Model S folks who have experienced THC_d0013 have replaced their battery heaters and not solved this issue. The battery heater is one of the early HV subsystems that is not included in the HVIL* -- a safety feature -- so be very careful if you unplug it. It's supplied HV power from the DC-DC Converter, and its plug is readily accessible there, right up top. You can test the heater for correct internal resistance ranges.
From the Service Manual, section Engine-Hybrid System, Cooling, HV_Battery Coolant Heater
That will give you a rough idea if the heater's close to being functional, but it doesn't test for HV isolation, and THC_d0013 covers a lot of different scenarios. But I wouldn't be surprised if it passes that crude test.
I think I'd check the heater against that chart of values first, then probe the output of the DC-DC Converter for an open fuse. That requires knowing a baseline resistance value of that circuit inside the DC-DC -- which I don't have ATM -- and definitely remove the HV Service Disconnect from under the passenger seat, because the system can activate the DC-DC at any time. Never probe any DC-DC HV connections unless the Service Disconnect has been removed.
If you want a baseline fuse check resistance, maybe Vlad has it (or it's somewhere in the Service Manual, and I just haven't found it). If not, I can get it from one of my RAV4 EVs in a day or two.
From what I see, aside from damaged wiring, the heater itself can cause that DTC, a failed fuse inside the DC-DC, or the DC-DC itself. That's on the HV side of things.
On the LV/sensor side . . .
. . . there are other things to check out. I lack the time right now to look into this deeper . . .
* = This is not strictly true: the mating plug on the battery heater harness does have an HVIL loopback, so unplugging it ought to open the HVIL and prevent HV contactor closure. What I meant is that the HVIL does not extend all the way to the individual components: battery heater, AC compressor, and cabin heater. But their harness KET connectors at the DC-DC do include HVIL loopbacks . If you're interested in learning more about this, see the excellent Tesla Service Bulletin SB-10052460-6095 / TN-13-44-001 "Tech Note: Troubleshooting Isolation Faults".
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Checking resistance of DC-DC Converter Battery heater output with different polarity of DVOM connection.
https://alflash.com.ua/2019/to_rav4ev/bat_heat.jpg
https://alflash.com.ua/2019/to_rav4ev/bat_heat1.jpg
https://alflash.com.ua/2019/to_rav4ev/bat_heat2.jpg
Excuse me, but as I know this table shows the dependence of Battery Heater temperature sensor resistance...
https://alflash.com.ua/2019/to_rav4ev/heat_thermist.png
The results of the heating element resistance test will be interesting.
As I remember, its resistance is several tens of Ohms.
Update.
https://alflash.com.ua/2019/to_rav4ev/hvil_pins2.jpg
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dogger23
Member
Take a look
Note.
DC-DC converter assembly enclosure and supplies high voltage from the electric vehicle battery assembly to the
compressor assembly with bracket, battery coolant heater (uses 20A fuse, the bottom one in this photo*) and No.1 heater with bracket sub-assembly.
The DC-DC converter assembly controls the power source to the battery coolant heater using a signal from the thermal control ECU.
https://alflash.com.ua/2019/to_rav4ev/d0013.jpg
*
https://alflash.com.ua/2019/to_rav4ev/fuses.jpg
I look a cursory glance under the hood and didn't see the heater, it may be under plastic covers or under my jDeMO adapter. Do you have a a clue what kind of fuse that is? You mentioned 20, but I looks like a ceramic. I'll look in the manual for more info.
This heater is "well hidden". Follow the hoses and you will find it.
https://alflash.com.ua/2019/to_rav4ev/bat_cool4.png
Update . The specified fuse is located on the main board of the DC-DC converter https://alflash.com.ua/2019/to_rav4ev/fuses.jpg
1/2 Off Battery Heater Current
p.s. It would be useful to check the resistance of the heating element. Of course, with all safety rules.
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dogger23
Member
This is very helpful, but it seems with my after market modification, the convertor was moved, which explains why I didn't see it. I'll try and make more progress on the weekend.
Sir, this is my video answer to your question about the battery heater. And about the location of the DC-DC converter, you could find out from this link, which was recommended earlier https://alflash.com.ua/2019/to_rav4ev/bat_cool4.png
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dogger23
Member
A drawing of the structural diagram of the cooling accumulator was shown at the Toyota training. But this is not a photo of the under hood space. They are easy to find on the site using the search.
https://www.myrav4ev.com/threads/another-dead-rav4-ev.2582/#post-30340
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