Sparky

Here's how I see all the new posts in all the forums without missing any: Go to: http://fordcmaxhybridforum.com/ Choose "View New Content" on the right side of the page. Scroll down, and on the left, choose "Forums" and select a time period, "Past 24 Hours", or whatever. You will see posts in all catagories, from the last 24 hours. Posts unread by you will be: Bold

The only way for a voltage test to be accurate is with the battery disconnected and after the surface charge is dissipated. If you are testing with the car door open, the interior lights will cause a voltage drop. If you test at the jumper cable connection points under the hood, after the car has been unused for several hours, you will get a fairly accurate state of charge. The cables extending from the jumper points to the battery are so large that voltage drop is insignificant. Warning: Disconnecting the battery will cause loss of programming! The most accurate method to determine the state of charge is by measuring the specific gravity of the electrolyte. This is done by removing a cell cap and withdrawing some solution with a hydrometer. http://www.amazon.co...ds=E-Z Red S101

The OEM battery is a Motorcraft BXT-67R. CCA-390 RC-65. The last 3 (67R) is the BCI Group Number. Search for a BCI Group 96R battery. This battery is listed on page 350 in the owners manual. An example is the Motorcraft Part Number: BXL-96R, or NAPA 8496R. For this battery the CCA is 590 and the RC is 95. The 96R has 50% more capacity than OEM. http://pages.suddenl...ages/cmax04.jpg http://pages.suddenl...ages/cmax05.jpg http://pages.suddenl...ages/cmax06.jpg

Sign on the back of my motorhome: I may be slow, but I'm ahead of you.

The lithium traction battery is probably not taken below 80% discharge. The lithium battery is used to start the internal combustion engine. If this battery is dead you are in big trouble. An Energi could be plugged in to charge, but a Hybrid would have to be towed to create regen charging, if that is possible.

Recent information indicates that Ford engineering thinks the dead battery problem is related to the 4.2" LCD display in the center of the dashboard. Perhaps the survey could add the questions: 4.2" center LCD display and 8" center LCD display

This is for the 12v system.

FCDIM - Front Control/Display Interface Module (4.2" or 8" center LCD display)

While being towed, the CVT transmission is turning, it requires lubrication and cooling. Could it be the 12v electric transmission coolant oil pump running while being towed? A recording amp-meter would show that. (I have one.)

The C-MAX has terminals under the hood for jumper cable connection. See page 255 of the owner's manual. I would definitely connect these to the 12v system on the motor-home. This will keep the C-MAX 12 volt battery charged. When (not if) you replace your 12v battery, ask the dealer for a Motorcraft BXT-96R-590. This battery is listed on page 350 of the owner's manual. The 96R has 590 CCA and 95 RC, 50% more capacity than the OEM BXT-67R. If your battery has been completely discharged more than a few times, it will probably not pass a battery load test. Your OEM battery has a free replacement warranty for three years. The C-Max has parasitic loads which are not completely understood, such as the high voltage battery cooling fans. The fans (12v ?) draw air from the car interior to cool the lithium battery. If the interior air becomes too warm, the system may start the air conditioner to provide cool air for the lithium battery. See page 179 and 184 of the manual. The transmission has an electric coolant oil pump. There is an electric vacuum pump. Questions: Is vacuum used for power brakes, and is the vacuum maintained with the system off? For more info, see "Battery temperature controls": http://ev.sae.org/article/11705

APPS – Acceleration Pedal Position Sensor BEV - Battery Electric Vehicle BPPS – Brake Pedal Position Sensor (master cylinder pressure) BSCM – Brake System Control Module CARB: California Air Resource Board CCA - Cold Cranking Amps @ 0 degrees F DTE - Distance To Empty ETM - Engineering Test Mode PRNDL – Transmission Range Sensor SC – Speed Control TCM – Transmission Control Module UOA - Used Oil Analysis

Thanks for your info, I have amended my post,

Understanding your C-MAX 12 volt battery. The OEM battery is a Motorcraft BXT-67R. The last 3 (67R) is the BCI Group Number. The Battery Council International Group Number defines its dimensions, voltage, post configuration and terminal type. This BCI number battery appears to be Motorcraft only. I was unable to find another manufacturer offering a 67R battery. This battery is listed as having 390 Cold Cranking Amps (CCA) and a Reserve Capacity (RC) of 65. The Amp Hour (Ah) rating is not listed and may be about 35. (A 2012 Ford Explorer uses a BCI Group 65, CCA-750, RC-140) RC and Ah are not the same. RC is a estimate of time, the number of minutes (65) a battery can maintain a useful voltage under a 25 ampere discharge at 80° F, lower temperatures mean less capacity. 25 Amps x 12 volts = 300 watt load. A 300 watt load applied for 1.08 hours = 324 Watts or .324 kilowatts. The Ah rating for an automotive battery is usually based on a 20hr discharge at 80° F. For example, if a 12 volt battery at 80° F delivers 1.75 amps for 20 hours, its Ah capacity will be: 1.75 A x 20 hours = 35 AH. 1.75 A x 12 V = 21 watts. 21 Watts x 20 hours = 420 watts or .420 KW. Yes, you get more if you use it more slowly: Peukert's law. The 2010 Fusion (and others) use a BCI Group 96R battery. The dimensions are the similar. An example is the Motorcraft Part Number: BXL-96R. For this battery the CCA is 590 and the RC is 95. This battery may not fit in the battery box. I am not recommending this battery, just saying it is available. Using this battery may void your warranty, ask your dealer. The 96R has 50% more capacity than OEM, but it still can be drained by parasitic loads. When I change batteries or clean the posts, before disconnecting the cables, I connect my jump-start pack to an always-on 12v accessory port or other hot wire. This keeps the system powered up and I do not loose programing on the radio or reset trouble codes. I am careful to insulate the disconnected (hot) positive cable with a dry leather glove. Disclaimer: Read the warning labels. Electricity is dangerous. Wear eye protection.

A search for C-max battery problems turned up the following from a British C-Max owner. It appears this was a problem nearly 4 years ago. http://www.cmaxownersclub.co.uk/forum/technical-39/dashboard-lcd-clock-draining-battery-5912/ 07-30-2009, 02:53 PM "I had the alternator output checked and that is fine, the battery is only 18 months old and the supplier assures me that he doesn't get problems with these items, he really did sound genuine, very helpful chap! Last Saturday night I locked the car to notice that the dashboard LCD display and the clock display on the Sony radio were still illuminated. I unlocked and locked the car again and they did not extinguish. I said to the missus that if the battery was dead on Monday morning, I think I might know whats causing it, sure enough it was dead. The question is, could these two displys remaining on conceivably drain an 18 month old 62Ah battery in 36 hours?? If so, has anyone experienced this before and/or know what could be causing the problem?"

For the benefit of those testing their batteries using a digital volt meter, I conducted a test this morning. Since I don't have my C-MAX yet, I tested my Subaru Forester. This test is an example of what you should see when testing your C-MAX. The Subaru is 4 years old. The battery was replaced one year ago. It has had no electrical problems or dead batteries. The original battery was replaced after 3 years as normal maintenance. After sitting outside (33'F) overnight, the voltage was 12.5v. With the interior lights on the voltage dropped to 12.2v. After starting, the charging voltage went to 14.8v. After running for 15 minutes, the voltage had stabilized at 14.4v. Measured charging current after starting was 30+ Amps, slowly dropping to 25A after one minute and 4A after 15 minutes. The engine was shutdown and the voltage was 13.2v. Over the next hour the surface charge slowly dissipated and voltage dropped to 12.6v. By actual measurement the interior lights draw 3 amps. Opening the door caused a voltage drop of about .25 volt. If you have LED lighting it will be much less. Another test is to check your voltage with the system on, ICE running and not running, and lights, defroster, radio, etc. on. Your voltage should not drop below 14 volts. Using the defroster may cause the ICE to start. The engine does not charge the 12v battery, but will charge the high voltage lithium battery. I am happy to test a C-Max for anyone in the Auburn, California area.

The voltage test is only valid after the surface charge is gone, either by waiting 6 hours after charging or by placing a load on the battery such as headlights for ten minutes. If the battery is discharged the surface charge will be removed more quickly. Any load, even interior lights will affect the voltage reading. The most accurate method to determine the state of charge is by measuring the specific gravity of the electrolyte. This is done by removing a cell cap and withdrawing some solution with a hydrometer. http://www.amazon.com/E-Z-Red-S101-Battery-Hydrometer/dp/B000JFHMRU/ref=sr_1_1?s=automotive&ie=UTF8&qid=1362618805&sr=1-1&keywords=E-Z+Red+S101 Percentage Specific Voltage of Charge Gravity 100 -------- 1.277 -- 12.73 90 ---------- 1.258 -- 12.62 80 ---------- 1.238 -- 12.50 70 ---------- 1.217 -- 12.37 60 ---------- 1.195 -- 12.24 50 ---------- 1.172 -- 12.10 40 ---------- 1.148 -- 11.96 30 ---------- 1.124 -- 11.81 20 ---------- 1.098 -- 11.66 10 ---------- 1.073 -- 11.51 The removable cell cap has a cross allowing it to be removed with a coin. A cap is visible in the picture below. The other caps are under the label. The battery electrolyte contains sulfuric acid. A drop will eat a hole in fabric or paint. Use rubber gloves and eye protection. Acid can be neutralized with a solution of baking soda dissolved in water. The C-MAX battery, BXT-67R, has a sight glass (battery eye) on the top center of the battery. Observing a green ball in the sight glass indicates a charged battery. A red ball indicates discharged. http://pages.suddenl...ages/cmax04.jpg http://pages.suddenl...ages/cmax05.jpg http://pages.suddenl...ages/cmax06.jpg If after driving, you suspect your battery is low, I suggest charging it with a good microprocessor controlled battery charger. Take note of how long it takes to complete the charge. I have had good results with the Schumacher xcs15. This charger has a display of percentage of charge while connected. A battery left in any state of discharge, even for a few hours, will begin to sulphate and capacity will be lost. The battery's lifetime will be months rather than years. After reading many accounts of dead batteries in both C-MAX and Fusions, It is my humble opinion that the batteries are not being fully charged by the DC-DC converter. I think some hybrids are driving around with half discharged batteries. Even when the car is shutdown there is the constant load of the cellular / GPS / MFM modules, admittedly small and necessary, but over time will discharge the battery. The C-Max Battery appears to have less than half the reserve capacity of a similar non-hybrid. The battery dimensions are 9 1⁄8 x 6 15⁄16 x 6 15⁄16. It does not appear that a higher capacity battery would fit in the space provided. I do feel the battery is adequate provided it remains fully charged. Excellent primer on battery maintenance: http://www.autoshop101.com/forms/hweb4.pdf

I don't understand: "Idled it for an hour..." Did you wait an hour and test again? or run the gas engine for an hour? Leaving the headlights on for 10 minutes with the system off should remove the surface charge and leave the battery at 95% - 12.5v at least. As I understand it, the C-MAX uses a DC to DC converter in place of an alternator to charge the 12v battery. It appears that the DC to DC converter puts out 14.4 volts as it should. A laptop computer charger may have an output of 14.5volts at 5 amperes. Connect this to a C-Max and it might charge the battery in 10 hours, if there was no load. To check the current output of the DC-DC you need a clamp-on dc amp meter. Most clamp on meters do not do DC Amps. They are fairly expensive. You place the clamp around either battery cable and read the amps, charge or discharge. Here is an example: http://www.sears.com/craftsman-digital-clamp-on-ammeter/p-03482369000P The DC-DC converter should be able to power all lights and accessories and still put 30 amps into a discharged (12.4v) battery. My point is: The DC-DC converter may have the voltage, but not the Amps (current) to fully charge the 12v battery within a reasonable amount of time (15 minutes). I would hope the DC-DC converter puts out 50Amps (720 watts), to restore the battery to full charge quickly. The Ford engineers may have said "We have no 12v engine starter, so we do not need a big 12v battery or high capacity DC-DC converter." Think of electricity as water: Volts equal water pressure. You can have pressure with no flow when the valve (switch) is off. Amperes equal flow as in 5 gallons per minute from a garden hose, or 500 GPM from a fire hydrant. The pressure (voltage) is the same. Watts or Kilowatts equals gallons you used.

I'll take a guess at one acronym. GPSM = Global Positioning System Module The C-MAX SE with 200A includes:SYNC W/ MYFORD and SOS POST CRASH ALERT SYS. The post crash alert system transmits the GPS location of the car. This means the car has a cellular module and GPS. I found this on the Internet, so it must be true: "Through the new MyFord Mobile smartphone app, using the embedded AT&T wireless connection, Ford Electric vehicle owners will have the ability to send and receive data about their car providing command and control of vehicle settings while away from it. MyFord Mobile allows drivers to locate the vehicle with GPS, remotely start the vehicle and remotely lock and unlock the car doors using their smartphone. This is all done via AT&T's network through a cellular module in the car. When you buy your Ford EV, a 5-year subscription to the app is included, after which point you'll be charged a fee." In light of the above assumptions, the cellular module and GPS module must remain on even when the car is off and locked. (You are able to find the location and unlock the car). I will have a big grin the first time my wife calls to say she locked the key in the car. I know you can't, but if anybody can, she will. GPS always knows the time and what time zone you are in. If the C-MAX is in an area of no AT&T coverage, the cellular module will constantly try to contact a tower, using more power. This cellular/GPS module should not be able to drain the 12v battery in a week or two. MyFord/Sync is capable of connecting to Wi-Fi, so a Wi-Fi module may be alive when the car is off.

Max Power, thanks for the info you provide. If you do not see 14.1 - 14.4 volts during your commute, your battery is never fully charged. After a full charge and shutdown, without any load voltage drops quickly to 13.2V (surface charge) and then over the next 6 hours (+/-) to 12.6 V. The voltage drop you are seeing in the first 4 hours is dissipation of the surface charge, and not necessarily caused by load. During charging, the surface of the lead plates have a higher voltage, over time the surface charge is absorbed by the plates, or is removed by discharging with a load. To remove surface charge the battery must be discharged for several minutes. Using headlights with the system off will work. After turning off the lights, you will see a more accurate voltage. Lead-acid batteries are made up of plates of lead and separate plates of lead dioxide, which are submerged into an electrolyte solution of about 35% sulfuric acid and 65% water. As the battery discharges, the acid of the electrolyte combines with the materials of the plates, changing their surface to lead sulfate. When the battery is recharged, the chemical reaction is reversed. The acid is returned to the solution and lead sulfate reforms into lead dioxide and lead. Continuously operating a battery in a partial state of charge results in the accumulation of lead sulfate (sulfation) on the plates. Sulfation reduces the performance of the battery and may cause premature battery failure. I look forward to the results of your testing.

I do not own a C-MAX yet. I do have a good understanding of electricity. In reading this long thread, I see very few know the condition if their 12v battery. The easiest way to tell is with a digital volt meter (DVM). Harbor Freight has cheap DVMs for about $5. For most cars, while the engine is running and charging the battery, the voltage will be 14.2 to 14.5 volts. After the battery has been unused for 6 or more hours, (to allow the surface charge dissipate), the fully charged voltage should read 12.6 to 12.7 volts. 12.2v = 50% charge, 11.5v = dead and the battery will suffer damage, shortened life. The C-Max uses the 12v system to power all lights, blowers, audio systems, etc. (The air-conditioning compressor, heated seats and power steering may be powered by the high voltage lithium battery.) Conventional cars use a 100 Amp. (1,400 watt) belt driven alternator to carry the load and maintain a charged battery. If you are stuck in LA freeway traffic, you may spend considerable time creeping along with the ICE not running. Thats good, but what provides the 12v power? The answer is a DC-DC converter. This solid-state device must have the capacity to power all the loads listed above and maintain a full charge on the 12 volt battery. You may connect a DVM to an old 12v accessory plug, plug it into the dash and measure your cars voltage. Check voltage with the ICE running, ICE off, system shut down and after a nights rest. This DVM can also measure DC Amps up to 10A. Connecting the Digital Amp Meter in series between the negitave battery post and the disconnected ground cable will show even the smallest current draw (.001 amps). I do not recommend doing this as you may loose programming when the cable is disconnected. This would be a procedure performed by your Ford dealer to locate a source of power draw when the system is shut down. Photos are of my Chevy: I don't have a C-Max. http://pages.suddenlink.net/rwg/images/cmax01.jpg http://pages.suddenlink.net/rwg/images/cmax02.jpg http://pages.suddenlink.net/rwg/images/cmax03.jpg