my Toyota Corolla E170 (2013-2019) battery dies overnight what could be wrong

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal for safety.
• Required Tools: OBD-II scanner, multimeter, socket set, wire brush, and safety gloves.

2. Battery Inspection

• Inspect Battery Connections:

  • Remove the battery terminals (negative first, then positive).
  • Clean the terminals and battery posts with a wire brush.
  • Reconnect the terminals securely.

• Test Battery Voltage:

  • Use a multimeter to measure the battery voltage; it should be around 12.6 volts when fully charged.
  • If the voltage is low, consider replacing the battery.

3. Alternator Testing

• Check Alternator Output:
  • Start the vehicle and measure the voltage across the battery terminals with the multimeter.
  • The voltage should be between 13.8 and 14.4 volts. If it’s lower, the alternator may need replacement.

4. Parasitic Draw Test

• Perform Parasitic Draw Test:
  • Connect the multimeter in series with the negative battery cable and measure the current draw.
  • If the current draw exceeds 50 mA, identify and disconnect fuses one by one to locate the faulty circuit.

5. Repair or Replace Faulty Components

• Identify and Repair:
  • Repair any identified short circuits or replace faulty electrical components.
  • If the battery or alternator is defective, replace them as necessary.