The largest online repair guide library for every car

About us
Contact support
FAQ
Sign up
Sign in

Slower Supercharging & Range Drop on my 2018 Model 3 LR

0

Sarah K. · rep 0 · May 22, 5:22 AM · 1 replies · solved · Question

Vehicle: 2018 Tesla Model 3 Long Range

Hey everyone,

I've been noticing a significant change in my 2018 Tesla Model 3 Long Range lately. For the past few weeks, my Supercharging sessions have been much slower than usual. It used to hit peak speeds pretty quickly, but now it seems to taper off much faster, even when the battery is low and preconditioned.

On top of that, I'm seeing a noticeable drop in my overall range. My full charge used to get me a comfortable distance, but now it feels like I'm losing 20-30 miles compared to what I'd expect, even accounting for temperature changes. I'm usually charging to 80-90% at home.

Has anyone else experienced this with their older Model 3? Could it be a battery issue, or maybe something related to a recent software update? Any advice on what I should check or if this warrants a service appointment?

✓ Accepted solution

ClearTheCode Admin

ClearTheCode Team · rep 0 · May 22, 5:22 AM

0

ClearTheCode admin answer:

It sounds like you're experiencing a common concern for owners of older EVs, particularly regarding battery performance. Here's a breakdown of potential causes and what you can do:

  1. Battery Degradation: All lithium-ion batteries degrade over time and with use. This is a natural process that leads to a reduction in total capacity and can affect charging speeds, especially at higher states of charge. A 2018 Model 3 would naturally show some level of degradation.
  2. Battery Management System (BMS) Calibration: Sometimes, the car's Battery Management System can lose calibration, leading to inaccurate range estimates or suboptimal charging.
    • To recalibrate: Try running your battery down to a very low percentage (around 10-20%), then charge it fully to 100% and leave it plugged in for a few hours after it reaches 100%. Repeat this cycle a couple of times. This can help the BMS re-learn the battery's true capacity.
  3. Charging Habits: While charging to 80-90% is generally good, consistently charging to 100% or letting the battery sit at very low states of charge for extended periods can accelerate degradation. Also, frequent Supercharging can contribute more to degradation than slower AC charging.
  4. Software Updates: Tesla frequently pushes software updates that can sometimes alter charging curves or how range is displayed. While usually for optimization, it's worth noting if the issue started immediately after an update.
  5. Environmental Factors: Cold weather significantly impacts battery performance and range. Ensure your battery preconditioning is working effectively before Supercharging in colder climates.

When to see a shop: If the issues persist after attempting BMS recalibration, or if you notice any warning lights on your dashboard, a significant and sudden drop in range (more than 10-15% over a short period), or extremely slow charging even at low states of charge, it's time to schedule a service appointment with Tesla. They have proprietary diagnostic tools that can read detailed battery health metrics (like battery pack voltage imbalances or specific module issues) and determine if a component like a battery module or the charging system itself requires attention. While EVs don't use standard OBD-II codes for battery health, Tesla's internal diagnostics can pinpoint issues.

Menu

Help & account