Battery dead

[valkraider]

I have said this before, and will say it again. If there really is a difference on how the car behaves when the foot is on the brake during shut-down, they are going to have a lot (a LOT) of unhappy Ford customers.

 

So many people have been taught their entire lives to press the brake when starting or shutting down the car. Heck, it was even a staple of our drivers ed courses.

 

I highly doubt that having the foot on the brake during shut down changes anything.

 

I have tried it both ways and I have found no difference in the car behavior between the two. Whether or not my foot is on the brake, all the accessories and systems function exactly the same in my experimentation.

 

There has to be a ghost in the machine.

 

Ford reliability ratings and support costs would be horrific if something as simple as putting a foot on the brake at the wrong time can cripple the vehicle.

[darrelld]

It appears the 12v in the rear cargo area does not shut off, at least not as quickly as the one in the center console. It has been on over two hours now, so my assumption is it will not turn off. So don't leave things in the cargo area plugged in....

I will double check this in my C-Max Hybrid, behavior should be the same. The cargo area outlet would make an ideal jump point for my Stanley Simple Start.

 

Edited December 31, 2012 by darrelld

[Laurel]

Valkraider my husband agrees with you.  Since there is a ghost in the system somewhere, I will carry on with my foot off the brake routine.  I find it a struggle to remember as it does indeed go against standard safety procedures that are ingrained in all of us.  It will be fascinating to learn what the real issue is down the road.

[salman]

I have had my C MAX SE back since Friday with a new battery from the dealer, though no problem could be identified in the old battery. So far so good.

 

Meanwhile, I had the idea to Google for issues with the Prius and 12 volt batteries, and also with hybrids in general. And there are recurring issues. You can find this pretty easily on Google, but one especially informative piece is here: http://www.examiner.com/article/auxiliary-battery-woes

 

To summarize the contents of that article and other stuff I read: the 12 volt battery in hybrids is smaller, less powerful, and has less reserve capacity than in regular gas operated cars. In addition, the battery charges at a lower and slower rate of 3.5 amps, maximum. What this means is that 12 volt batteries in hybrids are much more prone to being drained out than in regular gas cars. Thus, if you use accessories when not driving  the car you drain power. Batteries lose charge over time with the car off, though the car should still start after sitting for 3 or 4 weeks (should is the operative word). Infrequent and short distance usage does not recharge the 12 volt battery sufficiently, and the batteries are more sensitive to this because of their smaller capacity. And I think it is also the case that these smaller batteries are more prone to damage when discharged. Each time a battery is discharged to the point of needing a jump/re-charge, it tends to lose total capacity.

 

Add all that together and throw in a car that may have been used for 1 and 2 mile test drives at a dealer, might have sat for a month or two, and maybe had a battery that was not 100% charged to start, and all the sudden a lot of what we have been experiencing becomes potentially explicable.

 

There might still be other problems behind some of our experiences, such as electrical malfunctions and batteries defective from the factory, but it seems easy to damage these batteries at a dealership and then make it worse early in the life of the car by fiddling with the accessories. Moreover, the Prius blogs tell stories of strange things happening when the 12 volt batteries are near the total discharge and/or failure point: lights turn on, doors unlock, etc.

 

Prius owners sometime buy after market batteries from Optima as replacements. They are supposed to be more robust than the original equipment. Some buy trickle chargers, but I think this needs care in terms of warranty coverage. Something to look into.

 

Ford seems oblivious to all this, so far as I can tell, but I expect to be talking with their customer care people again the end of the week and will discuss it with them.

Edited December 31, 2012 by salman

[dtorres]

Salman

 

I think you may be spot on. When I first got my C-Max I had a few minor electrical issues that stopped occurring after a few days (probably after the 12V battery had built up a good charge).

I then drove for 3 months without a battery issue (which included a daily work commute of 45 miles). I was on vacation in December and did projects around the house. For two weeks the only drives I did were short two mile trips to the hardware store. At the end of the two weeks dead battery. I jumped it right before a trip to San Diego (3 hour trip with plenty of time for the battery to charge) and have not had a dead battery since going on a week.

 

I think your right that a small battery and slow charge rate may be an issue combined with not enough driving to sufficiently recharge the battery.

[RachelnLa]

So that means we must drive more?!?! I am up for that lol

[andrewwx]

I dropped my Cmax off at Ford today. They gave me a loaner, which was nice. They are going to talk to The Ford Hybrid Engineering team and try to find some answers (I hope)

[erwhitham]

I've had 2 Priuses and put on very little mileage because of short trips (2007 with only 35,000 miles at trade in for CMax), and no battery issues-even after leaving it at the airport in dead of winter for 14 days. I certainly hope My CMax behaves as reliably with its 12 volt.

[salman]

Andrewwx

 

Please call Ford's Customer Service line, too, so Ford's central offices know this is a concern. That will ultimately help dealer service and us.

 

Erwhitham

 

On the Prius discussion boards there are lots of owners who say they have never had a 12 votl battery problem and can leave their care for 2, 3 even 4 weeks without driving and then start easily. That is the way it is supposed to be. But there are other posters who say their 12 Volt problems happen within days or less of their last drive. The causes could be a bad or damage battery, or a problem with the charging system, or a short that drains power, or something else that drains power, or a combo of these things. I think the Ford might be experiencing similar issues: no problems for many, mysterious problems for some of us.

 

The Ford customer service manager is supposed to be calling me tomorrow with the results of his research. I will share notes with him and report back on the conversation. Then I will fill in my local dealer, too.

[advsysal]

I'm really glad to have found this forum as my wife recently got the C-Max SE (key, not pushbutton start) and the battery has gone dead twice.

While we thought the first dead battery situation was a fluke, we were carefully watching to make sure that nothing was plugged in, all doors closed, etc, and had the issue again.

[CNCGeek]

I will double check this in my C-Max Hybrid, behavior should be the same. The cargo area outlet would make an ideal jump point for my Stanley Simple Start.

 

Neat little device there, I hope it works with a really dead battery.  I have a dead battery right now, and am gonna wait till the AM to jump it, but I noticed that the rear lift gate does not open from inside or out with the battery dead so putting the jumper in the rear storage may make getting it difficult when you actually need it.

[salman]

I'm really glad to have found this forum as my wife recently got the C-Max SE (key, not pushbutton start) and the battery has gone dead twice.

While we thought the first dead battery situation was a fluke, we were carefully watching to make sure that nothing was plugged in, all doors closed, etc, and had the issue again.

 

 

Advsysal -

 

Please add your details to the Dead Battery Roll Call Thread and, most important, please call Ford's Customer Service line to log your problem with them as well as with your individual Ford dealer. The Ford central number is posted earlier in this thread.

[darrelld]

Neat little device there, I hope it works with a really dead battery.  I have a dead battery right now, and am gonna wait till the AM to jump it, but I noticed that the rear lift gate does not open from inside or out with the battery dead so putting the jumper in the rear storage may make getting it difficult when you actually need it.

 

Thank for the dead battery hatch observation. I moved the Simple Start to a new location.

 

[PWBarrett]

Thank for the dead battery hatch observation. I moved the Simple Start to a new location.

 

 

 

Uh, I'm not recognizing that location from the picture - where is that?

[darrelld]

Uh, I'm not recognizing that location from the picture - where is that?

 

There is a hidden space underneath the rear floor mats.

[PWBarrett]

There is a hidden space underneath the rear floor mats.

 

Wow - I had looked in the right-side "smuggling compartment" a couple of times, but never bothered to look in the left one - I assumed it was the same.

Do you think you can get the jump starter out if the electric seat is all the way back and the battery is dead though?

[darrelld]

Wow - I had looked in the right-side "smuggling compartment" a couple of times, but never bothered to look in the left one - I assumed it was the same.

Do you think you can get the jump starter out if the electric seat is all the way back and the battery is dead though?

Tested it with seat all the way back and no problems removing the Simple Start.

[HPRifleman]

In cases where the 12v battery has been discharged, I don't quite understand those of you that say you are "jump starting" the car.

 

Conventional automobiles with dead batteries require a lot of current from another vehicle so that the starter motor can turn over the gasoline engine. That's what I consider jump starting.

 

The C-Max doesn't utilize a normal starter motor. My understanding is that the 12v battery is just there to get the electronics going. If this battery has been depleted all that would be required would be to momentarily connect another 12v source in parallel to the dead battery and all the electronics should come back to life. Once that happens the battery gets recharged normally unless the battery cells are bad.

 

Is this actually how you are getting back on the road?

[PWBarrett]

I think it's just the closest existing term - Maybe we need a new one for this use-case.

[valkraider]

Not a full fledged jump. More of a hop.

[darrelld]

Temporary Supplementary Control Circuit Excitation?

[Bob999]

For those cases where the CMAX was dead or "failed to start" but no problem was subsequently found with the 12V battery I have a theory about what the problem might be.

 

I understand that the high voltage battery is electrically disconnected by relays when the car is shut off and that the same relays are activated to connect the high voltage battery when the car is "started".  I put started in quotes because the ICE doesn't necessarily start--starting is an electrical powering on process.

 

Based on my experience with other engines I know that the voltage required for a relay to activate varies by the brand of the equipment--for example I have a Deutz diesel where the starter solenoid (relay) won't activate if the voltage drops below 12 volts.  I have other engines where the starter will activate well below 12 volts.

 

So my theory is that perhaps some of the relays used by Ford to isolate the high voltage battery may be very sensitive to voltage--if voltage drops they don't work.  The voltage drop could be from a slightly discharged 12v battery or could be as a result of a poor connection somewhere in the circuit between the 12v battery and the relay (or in the ground circuit).  It could be a combination of both.

 

The fact people are able to "jump" the system with a very small capacity starter battery like the Simple Start is consistent with the theory I have advanced.

[PWBarrett]

Except that the posters talk about the whole car being dead, even the door locks.

There have also been some who measured <6V on the battery.

[darrelld]

 

 

 

 

Edited January 7, 2013 by darrelld

[darrelld]

deleted

Edited January 7, 2013 by darrelld