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Discussion Starter #561
Good to know - thx! Is this spec for a fully charged pack at no or minimal load? Load and low SOC both tend to increase the spread.
12. Verify each cell group voltage reading is between 3.28-4.16 V.
If not within the specified range - Replace the C4A Hybrid/EV Battery Section 1.
If within the specified range:
13. Verify each cell group voltage reading is within 0.03 V of each other.

If greater than 0.03 V - Replace the C4A Hybrid/EV Battery Section 1.

Oddly, it makes no mention of the SoC, and considering the voltage range is that of empty..full, I assume it means over the course of the entire SoC.
 

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Discussion Starter #562
PID question - There are a few PIDs listed for "Air Temp" and "vent temp". Are any of these confirmed to be the cabin air temperature as currently sensed?
Air temp is outside air. Vent temp is likely the actual vent temperature but I need to double check.
 

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Discussion Starter #563
Has anyone created custom PIDs to show max and min cell voltages? I see Torque Pro provides MIN and MAX functions but running all 96 voltages through would make for a pretty big equation (assuming one can use multiple functions in a single equation). I suppose you could also make many smaller comparison equations and then compare those in turn...but again, I don't know the intricacies of what Torque Pro allows. I thought I saw a post once where someone claimed to have implemented two such custom PIDs.
Not really useful. The system can only read about 15 PIDs/second. It takes 6 seconds to scan all the cells, not including anything else that is being scanned. The voltages will have changed by the time the scan is complete.
 

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Discussion Starter #564
Continuing, I believe that the Torque results on capacity are a bit low and should nominally be closer to 60KWh. I like the test of driving at 3.9mi/kwh @ 25C (77F) and seeing how many miles you wind up with. Use that result to calculate your actual KWh capacity.

Actually, just using your actual miles divided by average mi/kwh might be interesting to see.
I've run the car to empty a few times, and the result was within 1kWh of the claimed capacity each time. There are a variety of reasons, that I won't get into here, that I'm quite confident that the pack is actually 57kWh with ~60kWh usable - mainly because we don't use the pack anywhere near what a normal testing/labelling criteria is.
 

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Air temp is outside air. Vent temp is likely the actual vent temperature but I need to double check.
Has the PID file been updated with "Vent Temp" variable? The version I have lists Air Temp 0, 1, and 2 but no Vent Temp. Also, I wonder if anyone knows the location of those sensors. As far as I can determine, Air Temp 0 seems to "heat up" close to the battery temperature, while Air Temp 2 is identical to the temperature displayed on the infotainment screen.
 

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I have no Air Vent Temp. I concur, from trial and error, that Air Temp 2 is the closest to the info screen ambient air reading. The thermistor for that reading is located at the center of the lower grill, about a foot above the pavement.


There is a cabin air temp sensor, but no schematic to indicate where it might be.


There is also a humidity/temperature sensor behind the rearview mirror. But I have not determined if it corresponds to Temp 0, or 1.

 

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I have no Air Vent Temp. I concur, from trial and error, that Air Temp 2 is the closest to the info screen ambient air reading. The thermistor for that reading is located at the center of the lower grill, about a foot above the pavement.


There is a cabin air temp sensor, but no schematic to indicate where it might be.


There is also a humidity/temperature sensor behind the rearview mirror. But I have not determined if it corresponds to Temp 0, or 1.

Service manual for MY 2020 suggests there's upper and lower air temperature sensors:

B7BAir Temperature Sensor - Duct
Lower
In the passenger compartment, behind the instrument
panel, attached to the left lower HVAC duct
B7FAir Temperature Sensor - Duct
Upper
In the passenger compartment, behind the instrument
panel, attached to the left upper HVAC duct
B9Ambient Air Temperature SensorOn the front of the vehicle, to the right of the A/C
condenser, mounted in the grill
30243
30244

30245

You could point a heat gun in the direction of each of these and identify whichever one skyrockets to max rated temperature for the sensor
 

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Service manual for MY 2020 suggests there's upper and lower air temperature sensors:

B7BAir Temperature Sensor - Duct
Lower
In the passenger compartment, behind the instrument
panel, attached to the left lower HVAC duct
B7FAir Temperature Sensor - Duct
Upper
In the passenger compartment, behind the instrument
panel, attached to the left upper HVAC duct
B9Ambient Air Temperature SensorOn the front of the vehicle, to the right of the A/C
condenser, mounted in the grill
View attachment 30243 View attachment 30244
View attachment 30245
You could point a heat gun in the direction of each of these and identify whichever one skyrockets to max rated temperature for the sensor
Now that you've pointed them out, I was able to find the identical images from the MY 2017 service manual as well. Given that the Air Temp 0 and 1 values are generally close to each other, it seems highly likely that they are the duct air temperatures, although determining which one is "lower" and which one is "upper" would probably need a heat source as you said. Air Temp 2 would be "ambient temperature" and that makes sense as it should be the value seen on the infotainment screen.

Reading though the service manual, the point where the heater is automatically turned on is dependent on the duct air temperatures but not ambient temperature. So that seems to solve the mystery of why I need to adjust the temperature knob further down to prevent the heater from automatically turning on while the "Heat & A/C" button is toggled on.
 

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Given that the Air Temp 0 and 1 values are generally close to each other, it seems highly likely that they are the duct air temperatures
Everything you are saying makes perfect sense. If true, it should be very easy to check at least if they are the ones on the ducting. If the ambient air in my driveway is 95 F, Temp 2 will read ~95 F. I should be able to turn the Heat/AC to Low/ 61 F and see Temp 1, and Temp 0, drop dramatically. Can't say I recall anything that obvious, but I will pay attention to see.

If you were adventurous, you could pull the connector, remove the thermistor from the duct, reinstall the connector, and blow a heat gun right on the thermistor, while looking at Torque Pro.

 

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OK. The last few times we have been out in the car, I have been watching Torque Pro, from the passenger seat. Today was typical of what I see. Even though our logic is impeccable, things aren't working as anticipated. Taking off in the car when the outside temperature is in the 90's F, all three thermistors read with a degree of each other. I turn on the heat/AC to 72 F, all three vents on, and fan on 4. Torque Pro shows the AC compressor on and the heater on, as usual in this humid weather. I turn the temp to LO 60 F, and the heater goes off. The air coming out of the floor, chest, and windshield vents is very cold...but Temp 1, and Temp 0 are still within a degree of Air Temp 2. This is my memory of how they worked two years ago, when I first set up Torque Pro.

I have to believe the PIDs are not working correctly.
 
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