my Toyota RAV4 battery dies overnight, what can I do?

Solution

1. Preparation

• Gather tools: multimeter, ammeter, socket set, and cleaning supplies.
• Disconnect the battery before starting any electrical work.
• Ensure the vehicle is parked on a flat surface with the engine off.

2. Battery Inspection and Cleaning

• Sub-step 1: Inspect battery terminals for corrosion. If present, clean with a mixture of baking soda and water.
• Sub-step 2: Tighten battery terminal connections using a socket set.
• Sub-step 3: If the battery is more than 3-5 years old or shows signs of failure, consider replacing it.

3. Parasitic Draw Diagnosis

• Sub-step 1: Connect the ammeter in series with the negative battery terminal to measure current draw.
• Sub-step 2: Remove fuses one at a time to identify which circuit is causing excessive draw.
• Sub-step 3: Once identified, inspect the associated components for faults or shorts.

4. Alternator Testing

• Sub-step 1: Start the engine and measure the voltage at the battery using a multimeter.
• Sub-step 2: If the voltage is low, inspect the alternator belt for wear or looseness.
• Sub-step 3: If necessary, replace the alternator or repair connections.