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Regenerative Braking Limited at 68 Degrees

Regenerative Braking Limited at 68 Degrees

I live near San Jose, and we've had some cool mornings... but not what most folks would consider cold.
I've been seeing a number of times driving in both the morning and the evening stating "Regenerative Braking Limited"
And no... the battery is not full (always less than 90%)

Tech support is telling me that this limit is normal when the battery is below 20deg Centigra

johnse | February 22, 2018

Good data point.

If your mornings have been cool, I would assume the night was cooler. I would think the battery pack is colder than you might think.

jordanrichard | February 23, 2018

Limited at 68 deg F.....? Hmmm, shouldn't be. Now keep in mind I am driving a MS, but I wouldn't expect it to be that different. Regen limitation usually kicks in when the temps get down into the low 50's.

Bighorn | February 23, 2018

Looking at current San Jose weather, the evenings are high 30s/low 40s. Doesn’t matter if the temps warm up in the morning, you have a cold soaked battery. Low 50s is the threshold for regen limits.

andy.connor.e | February 23, 2018

thats really warm. Sometimes 68º is warmer than my apartment. That seems a bit much.

keichhor | February 23, 2018

Yeah I am in the Bay Area also. I had the same issue on a 119 mile journey. The "error" stayed until temperature was above 45F.

Tesla service said it was just a glitch and would probably clear itself if I was to exit the vehicle and re-enter.

MarylandS85 | February 23, 2018

I’m with @Bighorn on this one. It’s not the current temperature you should be paying attention to but the temperatures overnight. It takes hours for the batteries to cool or warm based on ambient temps. So perhaps the actual battery temp as you get ready to drive on your 68° morning is closer to the low temp overnight.

As a solution, if you’re plugged in, you can start charging or running the car’s heater to warm up the batteries, if you like. I favor the former so as not to waste energy. In the winter, I charge my Model S to 70-80%. As soon as I wake up, I start charging it to a higher level. While I get ready to go to work, it warms the battery a bit and improves regen.

BDBSE | February 25, 2018

I’ve had this message come up on the same hill at roughly the same location on the way down the hill. Battery far from overcharged yet about half way down the hill the message pops up and the car coasts freely down the hill. It almost seams like something gets warm from the regen process on a steep hill and causes the function to be disabled. A few minutes later after getting past the bottom of the hill the feature becomes available again.

BDBSE | February 25, 2018

It’s reoccurred at this same location several times, so it does not appear to be ambient temperature dependent.

Yodrak. | February 25, 2018

"It’s not the current temperature you should be paying attention to but the temperatures overnight. It takes hours for the batteries to cool or warm based on ambient temps. "

Does the Model 3 tell you what the battery temperature is? (My Leaf does, with LeafSpy.}

BDBSE | February 25, 2018

No it doesn’t, at least I’m not aware if it does. I just think it’s odd that it happens on the same steep hill at the same location on the hill, then comes back after a few minutes of being limited, once I’m on flat ground. It’s as though the amount of regen occurring on the steep hil is too much for the system to handle.

BDBSE | February 25, 2018

And it’s not occurring in the morning, we’re talking afternoon. Plenty of time for the battery to warm up.

rossh | February 25, 2018

The form has gotten so noisy. Glad to see Bighorn. He has a fan in very southern Arizona