why does my Ford Mustang S550 (2015-2023) battery die after a few days

Solution

1. Preparation

• Tools Required: Multimeter, OBD-II scanner, ammeter, safety gloves, safety goggles.
• Disconnect the negative terminal of the battery to prevent any electrical shorts and ensure safety.

2. Battery Replacement (if necessary)

1. Remove the old battery:

   • Use a socket set to remove the battery hold-down clamp.
   • Disconnect the positive terminal first, then the negative terminal.
   • Carefully lift the battery out of the compartment.

2. Install the new battery:

   • Place the new battery in the compartment.
   • Connect the positive terminal first, followed by the negative terminal.
   • Reinstall the battery hold-down clamp and tighten to manufacturer specifications.

3. Address Parasitic Drain (if present)

1. Identify the circuit causing drain:

   • With the ammeter in place, pull fuses one at a time to identify which circuit is causing the excessive draw.
   • Note the current reading and ensure it is below 50mA when the vehicle is off.

2. Repair or replace faulty components:

   • Inspect and repair any faulty components in the identified circuit, such as lights, modules, or aftermarket accessories.
   • If necessary, consult a wiring diagram for detailed troubleshooting.

4. Final Checks

• Reconnect the battery and perform a visual inspection of connections.
• Clear any stored fault codes from the OBD-II scanner.