2018 Ford Focus ST Owners Manual - Changing the 12V Battery

Changing the 12V Battery

WARNING:  Batteries normally produce explosive gases which can cause personal injury. Therefore, do not allow flames, sparks or lighted substances to come near the battery. When working near the battery, always shield your face and protect your eyes. Always provide correct ventilation.    WARNING:  When lifting a plastic-cased battery, excessive pressure on the end walls could cause acid to flow through the vent caps, resulting in personal injury and damage to the vehicle or battery. Lift the battery with a battery carrier or with your hands on opposite corners.    WARNING:  Keep batteries out of reach of children. Batteries contain sulfuric acid. Avoid contact with skin, eyes or clothing. Shield your eyes when working near the battery to protect against possible splashing of acid solution. In case of acid contact with skin or eyes, flush immediately with water for a minimum of 15 minutes and get prompt medical attention. If acid is swallowed, call a physician immediately.    WARNING:  Battery posts, terminals and related accessories contain lead and lead compounds. Wash hands after handling.    WARNING:  For vehicles with Auto-Start-Stop the battery requirement is different. You must replace the battery with one of exactly the same specification.

The battery is in the engine compartment.

 Your vehicle has a maintenance-free battery. It does not require additional water during service.

If the vehicle battery has a cover, make sure you correctly install it after cleaning or replacing the battery.

For longer, trouble-free operation, keep the top of the battery clean and dry and the battery cables tightly fastened to the battery terminals. If any corrosion is present on the battery or terminals, remove the cables from the terminals and clean with a wire brush. You can neutralize the acid with a solution of baking soda and water.

We recommend that you disconnect the negative battery cable terminal from the battery if you plan to store your vehicle for an extended period.

Note:   If you only disconnect the negative battery cable terminal, make sure it is isolated or placed away from the battery terminal to avoid unintended connection or arcing.

To maintain correct operation of the battery management system, if you add any electrical devices to your vehicle, do not connect the ground connection directly to the negative battery terminal. A connection at the negative battery terminal can cause inaccurate measurements of the battery condition and potential incorrect system operation.

Note:   If you add electrical accessories or components to your vehicle this may adversely affect battery performance, durability and the performance of other electrical systems on your vehicle.

If you replace the battery make sure it matches the electrical requirements of your vehicle.

If you disconnect or replace the battery and your vehicle has an automatic transmission, it must relearn its adaptive strategy. Because of this, the transmission may shift firmly when first driven. This is normal operation while the transmission fully updates its operation to optimum shift feel.

Remove and Reinstall the Battery

To disconnect or remove the battery, do the following:

1. Apply the parking brake and switch the ignition off.

1. Switch all electrical equipment off, for example lights and radio.

1. Wait a minimum of two minutes before disconnecting the battery.

Note:   The engine management system has a power hold function and remains powered for a period of time after you switch the ignition off. This is to allow diagnostic and adaptive tables to be stored. Disconnecting the battery without waiting can cause damage not covered by the vehicle Warranty.

1. Disconnect the negative battery cable terminal.

1. Disconnect the positive battery cable terminal.

1. Remove the battery securing clamp.

1. Remove the battery.

1. To install, reverse the removal procedure.

Note:   Before reconnecting the battery, make sure the ignition remains switched off.

Note:   Make sure the battery cable terminals are fully tightened.

If you disconnect or replace the vehicle battery, you must reset the following features:

• Window bounce-back.   See   Resetting Window Bounce-Back. 
• Clock Settings.
• Pre-set radio stations.

Battery Disposal

Make sure that you dispose of old batteries in an environmentally friendly way. Seek advice from your local authority about recycling old batteries.

Washer Fluid Check

When adding fluid, use a mixture of washer fluid and water to help prevent freezing and improve the cleaning capability.For information on fluid dilution follow the manufacturer's instructions.

Note:   The reservoir supplies the front and rear washer systems.