dmk2000

Plus 3 Golfer. Did a test following your procedure and here are my results. With car not ready to drive it shows 12,4 Volts. With car ready to drive with ICE off, it showed 13.7 Volts. You are correct, HVB does charges 12 V battery. That said, I cannot understand is why after driving for a straight 40 minutes, as soon as trying to park on a driveway transmission got stuck due to low voltage on 12 V battery, we are talking same moment as soon as start/shutdown button was pressed in order to turn car off not after it was left along overnight?. 40 min drive should be enough to charge even depleted battery. Do you or anyone have any suggestions what could it be. P.S. Same time as I was performing your test, I connected battery charger to see what state battery charge is. According to charger 12 V battery was 80% charged. Not sure if this is good or bad. Three weeks ago, dealer did diagnostic on battery and it passed.

Zathrus and Plus 3 Golfer, you could be right about potential issue with DC-DC converter on my CMAX. I will test Engineering Test Mode tonight. Will let you know. Thanks

Hello Everyone. Last Saturday, I had another reoccurring problem with 12 V battery right after driving it for at least 40 minutes. In my case due to lower voltage of 12 V battery, Transmission shifter relay got stuck and would not allow to be shifted to any gear. Anyways, checked battery voltage, and it was 12.1 V without load. I called Ford Road side assistance, upon arrival of a tow truck, I inform driver that last time ford Dealer told me that it was due to lower voltage on 12 V battery. Driver pulled out BIG and advanced jump pack with a build in tester for alternator and all. After connecting it to the car, and waiting for a few minutes we try to start car, and behold shifter start moving again. After I place gear shifter back in P, and pressed gas pedal to the floor, ICE started. During this time we still had this battery pack connected to the car, and tester showed that this battery pack started charging, and alternator status "PASS". However, when ICE turned off, tester showed that there is no charging occurring on 12 V system. What it tells me is that as of now the only time my 12 V battery will be charged is when ICE is on. Now it makes sense to me. If you are trying to keep CMAX on HVB power as much as possible, and minimize use of ICE, it might not have enough time to properly charge 12 V battery. This can be a PART of the reason why we have so many issues with 12 V battery. I am not calming that this is a reason, this is just an educated guess, also, when you are starting with not properly charged battery, every parasitic current draw whenever it is small or large, can overtime cause 12 V issues. As a temporary solution, I am starting maintenance charging 12 V battery on weekly bases. What a pain in the ***. Let put this way, until Ford comes up with proper solution to our 12 V battery issues, I tell everyone that my wife CMAX hybrid is actually plug-in.

Unfortunately, using this tactic can backfire. When giving suggestion to service department mechanics you might clash with their ego. It is like "who the heck are you to tell me what to do?". That said perhaps tech in your dealership might have open mind for an outside help. Good Luck.

Hi drdiesel1. Sound like a possible cause. Will try to find it.

Hello everyone. Well, it could be a fuel system as well, that said, why would it be on for over an hour? Same applied to cooling fan. I would expect it to be done withing minutes. I am thinking along these lines, if there is a reason to run some modules in a car after turned off procedure, it could be a high temperature of HVP, or fuel line pressure check, then by turning car on and off again should still keep these system running until conditions are right for turning them off. In my case, after "rebooting car" these activities are no longer present. If HVB cells are hot, then fan would still run till temperature is withing a normal range. Same applies to pressure maintenance on the closed system, I would expect it to resume as well until test is done. I was tempted to let it run till morning, but since I do not have a "backup car", and both of us need to be at the place of work in the morning, I had to stop it. As far as battery test, I did it using connection points in engine bay.

Last night it happened again. After coming from work, I parked my car and was walking to the house, when wile passing my wife's Cmax, I heard fainted noise from the back of the car. The same noise as someone here posted video of it. I walked in the house and ask my wife when did she came back. She told me it was over an hour. So I took my volt meter and went outside. Checked 12 V battery voltage and it was 12.5V. Good, battery is not dead. What I did is turned car on and then off. Guess what, noise is gone. This morning car started fine and she went to work. This leads me to believe if I would not take care of this sound, by the morning the 12 V battery would be dead. I incline toward the theory that HVB cooling blower in some cases prevents computer from totally powering car off, and in the same time keeps this blower on until 12 V battery is dead. Based on a HVB pack design, the noise is very likely coming from this cooler blower: I know this is a picture of CMAX ENERGY battery pack, but CMAX hybrid also uses this configuration for cooling. What do you think? Did anyone with 2014 CMAX seen similar issue?

Actually she is. One of the reason we bought this car is to get better mileage out of our gas $$. So if any change will further our cause, she is good with it. Advise on other matters such as kids, house remodeling, how to spend a weekend, what's for dinner, and other "minuscule" issues is another topic ;)

Here is an update. I ask my wife to maintain 67~68 mph as you recommended on eco-cruise and behold, she did get an extra mpg out of it. Granted, she only drives about 15 miles on a high way, but still, it is a nice bonus. Thanks for a tip. Personally I thought sweet spot is around 55~60 mph.

I am agree with you that cost of fuel is only a part of overall cost of owning car. For VW diesels ,you also have to factor maintenance cost. quality of VW cars is not uniform, and can varies from car to car. As I said before, I do not complain about mileage of CMAX, I am very pleased about it. However, in a winter month (North East) I do expect to lose some m/g, as it been happening with other gas powered cars, where diesels do not take such a big hit. That said, I also think that new diesel technology (clean air) is actually make diesels over complected and force mileage penalties. In a long run, hybrid might win. If I thought otherwise, I would go for a diesel. But again, if someone spend good part of the year driving in a cold climate, diesel could be an option.

Well, you are lucky to get these numbers. My wife only getting about 41,5 on freeway doing 65 mile per hour (still not complaining, and happy). I am afraid, that during winter time, she will not be that lucky. My buddy diesel seems to be immune from winter gas blend and lower temperatures. He gets constantly 50 or more miles per gallon on his WV diesel.

That what I was thinking about as well.

Well drdiesel1, I guess I has wrong. It was a copy of a bill dealer send to ford, not me. Should had read it more carefully first time. O well....

I am not planning give them anything. My line of thought is along your line, it is a new car with 1400 miles on it, that is why there is manufacturer warranty on it. They reprogram computer display to address 12 V battery, so why charge me and not FORD? I do not remember if R.O. had a $ amount. This is not my new car, other cars had their share of warranty repairs, but I was newer charged a penny, not even $5 a day for a loaner, it was inconceivable for me to think they will charge me for a repair under warranty that is not a consumable item. I am with you on sleazy dealers. If I wanted to pay for repairs, I would buy used out of warranty car.

This is true not just for hybrids. I lose about 4 mpg in winter even without such extreme temperatures on old good ICE. Do not forget that in a winter month gasoline blend also responsible for a mileage drop.

Here is another twist to the transmission issue. Coming home from work, got a $118 bill from a dealer for a labor of 12 V battery charging. Are they for real? Wow, just wow.

It is charger, cheep one, from garage sale. It has a lights, red when charging in process, and a green upon completion of a charge cycle. Not sure what Amp does it feed battery with.

Will do next time. That said, after turning car on and off, the noise is gone. That leads me to believe that if Li-Ion batteries where truly hot, this operation will still keep blower on after said procedure.

I just got my 2013 CMAX SEL from a dealer service due to a 12 v battery issue. They updated software for a display that prevented car to fully turned off. Said that, after coming back home, I parked CMAX, turned it off and was ready to walk away. Suddenly, I heard a noise from the back of the car, that seems to be originated from the bottom. Same noise as someone posted video on a forum. To me it sounded like a small blower fan. Turning car on and off again made this noise stop. To me it means that even if 12 V battery is in a good condition, by having this part running would drain the battery overnight. This is discouraging, especially on the same day as this car was supposedly fixed by the dealer. I also suspect it might be a High Voltage Battery cooling blower. It could be at the time of turning this car off, it was running, and for some reason computer aborted complete shutdown due to this running fan, perhaps to avoid Li-Ion cells from overheating. I believe it might be a cause for some 12 V battery issues.

Thank drdiesel1 for an advise. I do have a battery charger, I use it to maintain my ATV and backup diesel generator batteries. I guess I will start to use it on CMAX.

Hello Drdiesel1. Believe it or not, before picking up car from a dealer, I ask sales person to prep the car. The guy is a trustworthy. Before delivering it to me, they change the oil, checked for outstanding recalls, tested and recharged battery. Based on this info, I am not sure what is going on. On top of this, during four weeks of owning this car, it was never driven thou the rain.

Well, here is a final update. Picked up CMax. Technician told me that they performed TSB that addresses reprogramming information display that prevents car to fully turned off. They also checked battery, and fully charge it. Drdiesel1 was right, it is due to 12 V battery. I also notice in this car, when placing shifter to the park position, the "P" is light up. However the shifter has about 3/16" play. So, while it is in "P" position, if it moves down so slightly, the display no longer shows "P", and it looks like transmission does not engage in any gear. It only happens in "P". No other gear position have this. Can anyone else replicate this behavior of the shifter? Thank you.

Just got a call from service department. They told me that car is ready. When I asked what was wrong, they told me a 12 V battery. Hearing this, I ask that guy if he knew that when this happened, the car was driven 40 minutes, and also was on when this issue occurred. I also told him that after shutting car off, I could still use power windows. Also, the car could be successfully turned on with A/C on, all after this issue happened, except transmission was stuck. So the guy told me that since technician is gone for the day, he will talk with him tomorrow morning and then give me a call back. If it is indeed 12 V battery, then drdiesel1 is right. Said that, I feel this car is dangerous. If depleted 12 V battery causes this car not to engage park position properly, then when parked on incline, could it roll by itself anytime? Odd things.

Hello Crystal. Absolutely, I will let you and members of this board know about diagnostic results of this problem. Thank you very much for your support.

Hello Kastby. You are right, it is on dashboard, but location of this display is clearly visible and not obscure by the steering wheel. Said that, if you move the joystick to the bottom of the gate, it will be engaging D position, and not L. So from engineering point of view you are eliminating potential for choosing wrong gear.