Ford 2013 C-MAX ENERGI Owner's Manual page 288

When a low voltage battery replacement is necessary, see an authorized
dealer to replace the low voltage battery with a Ford recommended
replacement low voltage battery that matches the electrical requirements
of the vehicle.
To ensure proper operation of the battery management system (BMS), do
not allow a technician to connect any electrical device ground connection
directly to the low voltage battery negative post. A connection at the low
voltage battery negative post can cause inaccurate measurements of the
battery condition and potential incorrect system operation.
Note: If a person adds electrical or electronic accessories or components
to the vehicle, the accessories or components may adversely affect the
low voltage battery performance and durability and may also affect the
performance of other electrical systems in the vehicle.
Note: Always dispose of automotive batteries in a responsible manner.
Follow your local authorized standards for disposal. Call your local
authorized recycling center to find out more about recycling automotive
batteries.
Because your vehicle's engine is electronically-controlled by a computer,
some engine control settings are maintained by power from the low
voltage battery. Some engine computer settings, like the idle trim and
fuel trim strategy, optimize the driveability and performance of the
engine. Some other computer settings, like the clock and radio station
presets, are also maintained in memory by power from the low voltage
battery. When a technician disconnects and connects the low voltage
battery, these settings are erased. Complete the following procedure in
order to restore the settings:
1. With the vehicle at a complete stop, set the parking brake.
2. Shift the transmission to P (Park).
3. Turn off all accessories.
4. Step on the brake pedal and start the vehicle.
5. Step on the accelerator to start the engine.
6. Run the engine until the engine reaches normal operating
temperature. While the engine is warming up, complete the following:
• Reset the clock. See Clock in the Audio System chapter.
• Reset the radio station presets. See Number block in the Audio
System chapter.
• Reset the power windows bounce-back feature. See Resetting the
Bounce-Back Feature in the Power Windows section.
2013 C-Max Full Hybrid (34h)
Owners Guide gf, 2nd Printing
USA (fus)
Maintenance 287