THC_d0013 Coolant heater problem detected

[dogger23]

Since you have the connector off already, find a suitable probe (map tack, sewing pin, ball pin) and check the resistance between D9 (harness side) and ground. Vlad's posted chart at post #20 says it should be "approximately 240 ohms". On the white car, mine reads 254:

View attachment 871 View attachment 872


These are cheap and easy to use, either in the receptacle socket end, or to backprobe a connector if needed; I own some fancier probes, but I'm showing here that fancy isn't needed. A couple of clip leads, a sewing needle, and a decent ohmmeter.

View attachment 873

Doing this, my meter may be a bit wonky, but it goes between null values and 190, 180, 170 and 40.

 

[dogger23]

Mystery solved, thanks everyone, I'll update my post, once fixed.

 

[dogger23]

I put it all together, the car can go into "Ready" mode. It still says "Check EV system", but when I plug in my computer to the car, I have no faults. Resetting THC and gateway, has no effect. In my previous gas cars, I had to drive it for a bit to clear some errors, could it be like that?

 

[asavage]

Cycle the ON/OFF five times. The Toyota side tends to "hang on" to the P312F for a few cycles. I've seen three, others have seen five, but if you cycle the car ON/OFF more than five times and the "Check EV" remains, it's probably real.

The reason you have to drive ICE vehicles to clear some errors is because it's required to run some onboard testing to verify emissions requirements, and until it runs those tests, it can't declare the DTC "fixed".

One example: maintaining fuel tank vacuum. There's a spec that the tank vacuum must meet, like "must stay below this vacuum for ten minutes", so if there's a code set for that failing, it can't clear the code until it sees the correct vacuum level for ten minutes.

There are a lot of ICE situations like that. I'm not aware of similar time-related issues with our EVs, but they probably exist. But the "Check EV System" message remaining on the display is a known thing. However, it can also happen when using TPD 1.1.46 and certain DTCs that .46 doesn't show, such as BMS_w023 & DI_w115. So, it's possible it won't clear, but your TPD won't show you anything.

 

[asavage]

I'm interested in hearing that replacing the battery heater fuse fixes the original issue: THC_d0013. That is, if fuse replacement is a lasting fix for that DTC.

On the Tesla forum, I think I read somewhere that the original Zero Start brand battery heater (which our cars have) were later changed to a different brand, and when heat pumps were introduced later, the battery heater was eliminated altogether. A fair number of battery heaters have been reported as having failed and been replaced, but also a fair number of THC_d0013 DTC not being fixed by heater replacement alone.

Is yours just an old/weak fuse (like the OBC AC input fuse problem), or is is like the Cabin Heater, where the heater fails and takes out the fuse, and replacing the fuse doesn't solve the underlying issue? I'm interested in how your fuse replacement holds up.

I hope somebody makes up some nice, thick silicone gaskets for the DC-DC Converter.

 

[alflash]

I get null value for resistance between pin 5 and ground and 5 and 6.

If this check is with the D9 connector connected, then apparently this contact #5 of this connector in the battery (BMS) is connected to ground.
https://alflash.com.ua/2019/to_rav4ev/conn_d9.jpg

And between contacts #5 and #6 with the connectors or jumpers* inserted in the HVIL contacts, there should be a short-circuited circuit.
*
https://alflash.com.ua/2019/to_rav4ev/conn_i1_i2.jpg

 

[dogger23]

Cycle the ON/OFF five times. The Toyota side tends to "hang on" to the P312F for a few cycles. I've seen three, others have seen five, but if you cycle the car ON/OFF more than five times and the "Check EV" remains, it's probably real.

The reason you have to drive ICE vehicles to clear some errors is because it's required to run some onboard testing to verify emissions requirements, and until it runs those tests, it can't declare the DTC "fixed".

One example: maintaining fuel tank vacuum. There's a spec that the tank vacuum must meet, like "must stay below this vacuum for ten minutes", so if there's a code set for that failing, it can't clear the code until it sees the correct vacuum level for ten minutes.

There are a lot of ICE situations like that. I'm not aware of similar time-related issues with our EVs, but they probably exist. But the "Check EV System" message remaining on the display is a known thing. However, it can also happen when using TPD 1.1.46 and certain DTCs that .46 doesn't show, such as BMS_w023 & DI_w115. So, it's possible it won't clear, but your TPD won't show you anything.

Fixed it.

 

[dogger23]

I'm interested in hearing that replacing the battery heater fuse fixes the original issue: THC_d0013. That is, if fuse replacement is a lasting fix for that DTC.

On the Tesla forum, I think I read somewhere that the original Zero Start brand battery heater (which our cars have) were later changed to a different brand, and when heat pumps were introduced later, the battery heater was eliminated altogether. A fair number of battery heaters have been reported as having failed and been replaced, but also a fair number of THC_d0013 DTC not being fixed by heater replacement alone.

Is yours just an old/weak fuse (like the OBC AC input fuse problem), or is is like the Cabin Heater, where the heater fails and takes out the fuse, and replacing the fuse doesn't solve the underlying issue? I'm interested in how your fuse replacement holds up.

I hope somebody makes up some nice, thick silicone gaskets for the DC-DC Converter.

Yes, the original issue was solved simply by replacing the 20A 500V ceramic fuse. I ended up using a squeeze tube to reseal it. To clarify my car is the 2014, so it is possible I have a newer model heat pump. I ran the THC thermal test after I installed everything, and it passed that test. The fuse was set off, the multimeter showed no continuity between the ends. I'll be sure to return if the problem does, Everyone here has been very helpful.

Yeah, if Tesla used a silicone gasket, it would have avoided the issue of cutting the wires. I also heard Tesla puts in bad gaskets in their motors and coolant leaks into those, I'll take the safer option.

 

[dogger23]

If this check is with the D9 connector connected, then apparently this contact #5 of this connector in the battery (BMS) is connected to ground.
https://alflash.com.ua/2019/to_rav4ev/conn_d9.jpg

And between contacts #5 and #6 with the connectors or jumpers* inserted in the HVIL contacts, there should be a short-circuited circuit.
*
https://alflash.com.ua/2019/to_rav4ev/conn_i1_i2.jpg

I love the response, but for now it seems to work, so I'll let sleeping dogs lie. I really do appreciate any check that avoids opening up things if it can be helped, it did seem to show me that I had to open up the DC-DC converter.

 

[alflash]

...Vlad's posted chart at post #20 says it should be "approximately 240 ohms". On the white car, mine reads 254:

View attachment 871 View attachment 872...

The essence/content of this test is to confirm that there is no break in the HVIL circuit.
And the difference in the result from 240 Ohm is easily explained by the fact that in one of the three tested ECUs there is a break (usually due to a microcrack) in one of the 5 parallel HVIL SMD resistors.
https://alflash.com.ua/2019/to_rav4ev/hvil_.jpg
For example, when everything is intact/serviceable in the charger, then its HVIL resistance Rch = 300 Ohm : 5 = 60 Ohm. But if one is broken, then Rch = 300 Ohm : 4 = 75 Ohm (!!!) and 240+15 = 255/
Check, for example, the resistance of the HVIL circuit between pin # 6 and pin # 3 of the D4 connector of the charger. It should be 60 Ohm. It is possible that its value is 74-75 Ohm...
https://alflash.com.ua/2019/to_rav4ev/f008cause_fr.png

Note. This screenshot shows a fragment of the test plan description for this HVIL code(s) from program v.1.1.42.


1/2 off-topic. Came across this ancient micro video about HVIL on my channel

 

[asavage]

The essence/content of this test is to confirm that there is no break in the HVIL circuit.
And the difference in the result from 240 Ohm is easily explained by the fact that in one of the three tested ECUs there is a break (usually due to a microcrack) in one of the 5 parallel HVIL SMD resistors.
https://alflash.com.ua/2019/to_rav4ev/hvil_.jpg
For example, when everything is intact/serviceable in the charger, then its HVIL resistance Rch = 300 Ohm : 5 = 60 Ohm. But if one is broken, then Rch = 300 Ohm : 4 = 75 Ohm (!!!) and 240+15 = 255/
Check, for example, the resistance of the HVIL circuit between pin # 6 and pin # 3 of the D4 connector of the charger. It should be 60 Ohm. It is possible that its value is 74-75 Ohm...

That's really interesting, thanks! When the weather is better, I'll pull D4 off of the OBC and check that.

I assume you meant D4 pin #3 & 9, not 6?

1/2 off-topic. Came across this ancient micro video about HVIL on my channel

Haha! I like this part:



As if we have charge port temperature sensing, phbbt.

 

[alflash]

That's really interesting, thanks! When the weather is better, I'll pull D4 off of the OBC and check that.

I assume you meant D4 pin #3 & 9, not 6?

Haha! I like this part:

View attachment 879

As if we have charge port temperature sensing, phbbt.

1. I'm sorry about my typo Yes, the correct number of the other contact is No.9. Thanks for the correction.

2. This definition of CHG_w128 codes is from Tesla (from its scan tool) and I don't know what it means, because it's undocument code.
But alas, it is read from RAV4EV and both I and the client are completely confused/prostrated from not knowing the answers to the "eternal Russian" questions: "Who is to blame? and What is to be done?" (Russian proverb)...

Update. I don't understand this Tesla definition. Maybe you will find a description of this code in the Tesla documentation...