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I need help with information on the type of temperature sensors used in BMW battery modules. I have couple of failed ones and needs to replace them but could not get any leads on the type and value.

Thanks

This one? https://www.hubauer-shop.de/en/temperat ... 47873.html

That's the only temperature sensor that's listed for the HV batteries in the parts catalogue.

Thank you very much. The sensor I do require is the one directly on the batteries

Oh, this is not something you'll be able to get from BMW. They would replace the entire module.

But good luck. I suppose you'll need to characterize the sensor to find a replacement.

I've got a very rough approximation when working out ADC readings vs temperature. Check lines 92 - 101 here: https://github.com/mjc-506/bmsSerial/bl ... /PL455.cpp

Beta = 1000
Ro = 150 Ohm.
To = 290 (K)

I think I found a pretty close match when searching for these numbers. Good luck!

Thanks, will surely have a look at it. I tested a 3950 100k ohms NTC and seems to "work" as I got a a very close ambient temperature reading.

mjc506 wrote: ↑Thu Jan 20, 2022 9:58 pm I've got a very rough approximation when working out ADC readings vs temperature. Check lines 92 - 101 here: https://github.com/mjc-506/bmsSerial/bl ... /PL455.cpp

Beta = 1000
Ro = 150 Ohm.
To = 290 (K)

I think I found a pretty close match when searching for these numbers. Good luck!

Yes, those are much better numbers, not sure how I came up with mine then!!

Have been able to get the "exact" NTC used in the battery modules based on Deutronics HV charger manual. The NTCs are of 2 variant 100k/4.4 and 10k/3.4

Hello,

I have same issue with a G30 530e (SP06), i got this reading from Cell Module 2 checked at the connector at room temperature about 25 C,

Temp Sensor 1 90.8 K ohm (Pin 2 - 18)

Temp Sensor 2 1.2 M ohm (Pin 9 - 25)

Temp Sensor 3 91.6 K ohm (Pin 1 - 17)

Did someone here know if it is possible to change only the Temperature Sensor?

Thanks

Cell 3
Checked at the connector

Temp Sensor 1 87 K ohm (Pin 2 - 18)

Temp Sensor 2 125 K ohm* (Pin 9 - 25)

Temp Sensor 3 210 K ohm (Pin 1 - 17)

Cell 4
Checked at the connector

Temp Sensor 1 88 K ohm (Pin 2 - 18)

Temp Sensor 2 85 K ohm* (Pin 9 - 25)

Temp Sensor 3 104 K ohm (Pin 1 - 17)

Cell 5
Checked at the connector

Temp Sensor 1 88.3 K ohm (Pin 2 - 18)

Temp Sensor 2 87.6 K ohm* (Pin 9 - 25)

Temp Sensor 3 89.7 K ohm (Pin 1 - 17)

I think only cell module 5 is okay. The temperature sensor reading should be around 80kΩ to 92Ω but less than 100Ω for this particular sensors and any anything above it indicates a failure of the sensor. Module 2 (T2 is bad), Module 3 (T2 & T3 bad), module 4 (T3 is bad). Did you check this with a diagnostic tool to tell you the faulty sensors?

fatfash wrote: ↑Wed Dec 06, 2023 9:13 am I think only cell module 5 is okay. The temperature sensor reading should be around 80kΩ to 92Ω but less than 100Ω for this particular sensors and any anything above it indicates a failure of the sensor. Module 2 (T2 is bad), Module 3 (T2 & T3 bad), module 4 (T3 is bad). Did you check this with a diagnostic tool to tell you the faulty sensors?

As per scan Cell Mod 2. Is it possible to change the Temp sensor? Desolder the red glue and get a Temp sensor?
Thanks

Yes, you can change it.There is a procedure you have to follow to do this with BMW repair kit that includes the sensor. You can get the procedure from the ISTA you are using under " Repair Manuals and Technical Data / 61 General vehicle electrical system / 61 27 High-voltage battery unit individual component /"

fatfash wrote: ↑Wed Dec 06, 2023 5:24 pm Yes, you can change it.There is a procedure you have to follow to do this with BMW repair kit that includes the sensor. You can get the procedure from the ISTA you are using under " Repair Manuals and Technical Data / 61 General vehicle electrical system / 61 27 High-voltage battery unit individual component /"

But in BMW Pasrt Catalogue ther eis no sensor available, says complete battery cell

use this part number "61 27 8 849 422". A google search of this will show you what it looks like.

fatfash wrote: ↑Wed Dec 06, 2023 5:48 pm use this part number "61 27 8 849 422". A google search of this will show you what it looks like.

Great. WIll order same. Do i need some sort of calibration after this fix?

No calibration needed. Just follow the procedure of installing the replacement sensor and you should be good.

just be careful with the installation. Once the system detects you have opened the HV battery, the contactor will be opened and this will most likely require EOS tester to close the contactor.

fatfash wrote: ↑Wed Dec 06, 2023 6:23 pm just be careful with the installation. Once the system detects you have opened the HV battery, the contactor will be opened and this will most likely require EOS tester to close the contactor.

Ohh,
To start, I open the HV connector at the boot in order to work on HV (got message on cluster that HV is deactivated). Then I disconnect both 12 battery. After that, I removed the HV battery open it and test inside. So base on what i did, am not sure the system will know that I open the HV as all system are off.

let me know what you think about this. I do not have EOS.

This should be fine. Note also, the order of the cell supervision circuit and cell module are not swapped.

fatfash wrote: ↑Thu Dec 07, 2023 3:15 am This should be fine. Note also, the order of the cell supervision circuit and cell module are not swapped.

I already name them, so sure 100% no mismacth.

Nice

Do you have other pinging? I need for whole connector. Thanks