why does my Tesla Model 3 Original (2017-2023) battery lose charge while parked

Tesla Model 3 Highland (2024-present)

Error Codes

1-2 hours

Time

medium

Difficulty

medium

Severity

4 min read

602 words

Problem Statement

Learn how to diagnose and fix battery drain issues in Tesla Model 3 (2017-2023). Step-by-step guide with diagnostic procedures and repair instructions.

Affected Component

Electrical

Estimated Time

1-2 hours

⚠️ Safety Warnings

Important safety information - read before proceeding

•Ensure the vehicle is in 'Park' mode before performing any battery work.
•Always disconnect the battery when working on electrical components to avoid shock or short circuits.

Symptoms

•Significant battery percentage loss after a period of parking
•Notifications of low battery or range anxiety upon starting the vehicle
•Increased frequency of battery maintenance alerts
•Inability to access features like remote start or climate control due to low battery
•Potential updates or firmware notifications from the vehicle's system

Diagnostic Steps

1
Check the vehicle's battery state of charge through the Tesla app or vehicle display.
2
Inspect the Battery Management System (BMS) for any fault codes using the Tesla service mode or diagnostic tools.
3
Verify the settings related to energy-saving features in the vehicle's software.
4
Assess the status of 12V battery health, as a failing 12V battery can contribute to overall energy loss.
5
Review vehicle logs for any background processes or applications running that may be consuming energy while parked.
6
Confirm that all doors and systems (like trunk, glove box) are fully closed and not causing parasitic drain.

Solution

💡 Expert Tip

For complex repairs like this, consider taking photos at each step. This helps if you need to reverse a step or consult with a mechanic. Also, keep all removed parts organized - you may need to reference them during reassembly.

Verification

After completing the repair, verify that the issue has been resolved:

✓Test the affected component to ensure it functions correctly
✓Check for any error codes or warning lights
✓Monitor the vehicle for a few days to ensure the issue does not recur

Prevention Tips

To prevent this issue from occurring again:

•Follow the manufacturer's recommended maintenance schedule
•Address warning signs early before they develop into major issues
•Use quality parts and fluids recommended for your vehicle
•Keep detailed records of all repairs and maintenance

Tools & Equipment Required

•Multimeter
•Socket set
•Torque wrench

Parts Required

•New 12V battery compatible with Tesla Model 3

Related Faults

Share this solution

Comments

No comments yet

Be the first to share your thoughts

Back to Generation

Symptoms

•Significant battery percentage loss after a period of parking

•Notifications of low battery or range anxiety upon starting the vehicle

•Increased frequency of battery maintenance alerts

•Inability to access features like remote start or climate control due to low battery

•Potential updates or firmware notifications from the vehicle's system

Diagnostic Steps

1
Check the vehicle's battery state of charge through the Tesla app or vehicle display.
2
Inspect the Battery Management System (BMS) for any fault codes using the Tesla service mode or diagnostic tools.
3
Verify the settings related to energy-saving features in the vehicle's software.
4
Assess the status of 12V battery health, as a failing 12V battery can contribute to overall energy loss.
5
Review vehicle logs for any background processes or applications running that may be consuming energy while parked.
6
Confirm that all doors and systems (like trunk, glove box) are fully closed and not causing parasitic drain.

Solution

1. Preparation

Ensure the vehicle is parked in a safe location and that you have access to the Tesla app and vehicle settings.
Gather necessary tools, including a multimeter.

2. Inspect and Replace 12V Battery

Tools Required: Socket set, multimeter, torque wrench
Sub-steps:
1. Disconnect the Battery:
  - Open the front trunk (frunk) and locate the 12V battery.
  - Disconnect the negative terminal first, followed by the positive terminal.
2. Test Voltage:
  - Use a multimeter to check the voltage of the 12V battery. A healthy battery should read around 12.6 volts or higher.
3. Remove the Battery:
  - Unscrew and remove the battery bracket and carefully lift the battery out.
4. Install New Battery:
  - Place the new 12V battery in the bracket. Secure it with the bracket screws, ensuring it’s tightly fitted.
5. Reconnect the Battery:
  - Connect the positive terminal first, followed by the negative terminal. Ensure both are tightened to manufacturer specifications.

3. Update Software and Settings

Tools Required: Tesla app
Sub-steps:
1. Check for Software Updates:
  - Connect to Wi-Fi and navigate to 'Software' in the vehicle menu to check for updates. Install any available updates.
2. Adjust Energy Settings:
  - Go to 'Controls' > 'Energy' and enable ‘Energy Saving’ features.
  1. Turn Off Features:
  - Disable options that may cause battery drain, such as 'Sentry Mode' or 'Always Connected' features if not needed.