"Battery fequently goes dead and I have to charge overnite. Gasa mileage has nevermet close to sticker, s'ticker 47 mpg city and highway. (2013 Ford C-MAX Energi SEL 2.0-L 4 Cyl plug-in hybrid Pull the lever to open the trunk. If the battery is completely dead, you may need to use a jumper cable to start the car. Once the car is started, the trunk will open. If you can’t find the manual release lever, you can always call a tow truck or Ford dealer to help you open the trunk. According to the Ford workshop manual it says the 12V battery on hybrid models is under the hood and the main battery is in the trunk, but apparently that is incorrect and I will need to get that updated for future customers. Your 2017 Ford C-Max battery will typically last between 3 to 5 years, but that can vary heavily depending on type of battery, battery size, weather conditions and driving habits. Even still, just because your battery isn't entirely dead, doesn't mean it's operating accurately. For that reason, it is exceptionally important to have your battery My 2015 c-max won't start. It says no key detected. Mechanic's Assistant: Have you checked the battery, particularly the terminal connections? Are they corroded? Check battery no corrosion . lights horn and liftgate work. Mechanic's Assistant: What is the model of your '15 Ford? C-Max. Mechanic's Assistant: Are you fixing your vehicle yourself ACM battery drain. All, I have a 2016 cmax energi. I believe I have the audio control module battery drain. Its horribly annoying. randomly (usually if only used for a short drive, like moving the car for 15 seconds then turning off, something kills the lead acid battery. Sometimes it doesnt happen, and the battery will be fine a week later The battery goes dead a few days after taking delivery of new vehicle; this happens almost like clockwork every six months - resulting in many visits and 4 new batteries from 6/2013 until 1/2016. No dead battery now for 11 months. Ford always indicated we did something to cause these conditions. To expand on cr08's questions about the 12v battery status, I'd point out a few things. When a dealer [not just Ford but all major brands], is authorized to sell a model, they are required by guidelines to have on hand a certain amount of regular parts for upkeep of that model [filters, brake pads, batteries etc.] & the manuals & tools required. 1FI8sC.