how to diagnose and fix Tesla Model S Original (2012-2020) battery overheating

Solution

1. Preparation

• Tools Required: OBD-II scanner, multimeter, socket set, coolant pressure tester.
• Disconnect the vehicle’s battery for safety.
• Allow the vehicle to cool down before starting work.

2. Inspect and Replace Battery Coolant

• Sub-steps:
  1. Remove the front trunk panel to access the battery cooling system.
  2. Check the coolant level in the reservoir; if low, refill with the recommended Tesla coolant.
  3. Inspect the coolant hoses for leaks or blockages; replace if necessary.
  4. Use a coolant pressure tester to check for leaks in the system.

3. Replace Faulty Temperature Sensors

• Sub-steps:
  1. Identify the location of the faulty battery temperature sensor using the service manual.
  2. Disconnect the wiring harness from the sensor.
  3. Remove the sensor using a socket set.
  4. Install the new sensor and reconnect the wiring harness.

4. Tighten and Clean Battery Connections

• Sub-steps:
  1. Inspect all connections to the battery pack.
  2. Clean any corrosion from the terminals using a wire brush.
  3. Tighten all connections to the specified torque (refer to the service manual for values).

5. Update Vehicle Software

• Sub-steps:
  1. Connect the vehicle to Wi-Fi.
  2. Check for software updates through the vehicle's touchscreen interface.
  3. Follow on-screen instructions to complete the update.