Battery dead

[CNCGeek]

I picked up one of these for $50 at Home Depot:

 

http://www.blackanddecker.com/power-tools/JUS350B.aspx

 

It is certainly overkill, but I like having something which will work with my other vehicle and my family's cars too.  Jumping the C-max is a bit strange, as soon as I connected it, the car woke up, I was going to just let it sit there with the key on and not running since it seems that the 12v system will just charge off the HV battery (in fact once it woke up I took the booster off within a minute and it had no further problems).  The "hop" which was mentioned is much more descriptive than jump starting - it seems like it takes very little to get it going - and seems that the engine does not have to run at all to get it going again.  It did spit out some error about mykey and said max speed limited to 80mph briefly and then it got it's bearings and all the warnings cleared.  Since the HV battery was a bit low I took it out for a drive and have driven it several times since.  The voltage at the front was 5.5v when it died (forgot to check at the battery  - could not get to it anyway prior to jumping it). 

 

I think in my case the discharge could be due to accessories - I am not sure, but I do recall leaving a phone in the car charging on the 12V socket near the cup holders before this happened.  I had thought it would have powered down the outlet after some minutes, however that may not be the case.  The phone however should not have drawn off a huge amount of power - just a typical smartphone which was about 1/2 charged to begin with.  Likely it was the straw that broke the camels back though.

[Bob999]

A 12v lead acid battery with only 5.5 volts and no load is virtually totally discharged.  I hope you load tested the car battery it once you were able to access the rear.

 

I think the reason it doesn't take much to "start" the car with an auxiliary battery is that starting involves powering up the computer and reconnecting the high voltage battery via relays and it doesn't take much power to do that.  I think that once the high voltage battery is reconnected it provides 12v power via an electronic device.

 

But the fact that the car has operated normally since at least suggests that the 12v battery was not seriously discharged and causes me to wonder if there is another explanation for the very low voltage reading--perhaps there is a relay or other connection in the 12v circuit that is not making proper contact with the result that normal voltage is not available.

Edited January 8, 2013 by Bob999

[MichaelM]

I have a 2004 Thunderbird that has occasionally had a dead battery for no apparent reason (since purchased new about 4 times). It is a relatively frequent problem described on the forums. The main concensus is that there is some sort of problem with relays in the circuitry of the rear window defrosters that occasionally allow the battery to discharge through this circuit. I've not had the problem for a while now but they never fixed anything, that they told me about. The last time replacing the battery, saying it was not showing the correct CCA's.

 

I've not had a problem with the C-Max yet, but just want to 'relay' a bit of Ford experience.

Edited January 8, 2013 by MichaelM

[salman]

I heard back from the West Coast Ford Customer Care Manager. Here is my report on the conversation, with my own thoughts on the matter added along the way:

 

1)

He said that Ford's technical experts have received reports of an unspecific number of cases of 12 volt electrical systems gone dead and that the proper response to date has been to replace the battery, which, in my view, presupposes (maybe accurately) that problem is manifested in the battery. He did not specify a cause for the batteries going bad, just described the response to the symptoms that he said Ford has been finding effective.

 

In my view, if any of you have had 12 volt electric problems after a battery change out, then it is important that you let Ford's Customer Care line know about it. Your cases could help determine whether there is a problem with the battery out of the manufacturer or a problem elsewhere in the C Max electrical systems.

 

2) 

The Customer Care Manager also told me there is a new TSB, recently issued, advising Ford dealers to re-program the modules that send door & hatch open messages to the instrument panel. There seems to be a problem with these modules sometimes coming awake at odd times. The TSB is an advisory, not a recall. The technical experts recommend doing the re-programming if there are any incidents of trouble with the 12 volt system. Modules coming awake could drain some power, but in my view these modules should not drain much power.

 

3)

I told the Customer Care Manager what I had found by reading about 12 volt battery problems in other hybrids. Full description is earlier in this thread. Short recap: 12 volt batteries in hybrids are smaller and not as robust as in regular gas engine cars, more prone to being draining, and seem to be more prone to being damaged when drained. They re-charge more slowly, too. Consequently, a car at a dealership driven for 1-2 mile test drives that sits for a month and has its radio,, etc. fiddled with in accessory mode could have its battery drained and damaged.

 

The Customer Care Manager said that sounded like a plausible conjecture of what might cause the problems we have encountered.

 

I suggested dealers might make sure to charge up the 12 volt batteries when new cars arrive and maybe once a week if they sit on the lot to prevent deep discharging of the batteries. I also told him that Optima makes a supposedly more robust after market battery for the Prius. The Customer Care Manager responded to the second of these suggestions by saying that IF sufficient reports come in of battery problems related to the battery being too small in reserve capacity, then Ford potentially might design a more robust replacement battery that it might offer through a Customer Satisfaction Program. The highlighted words are there for accuracy's sake, not a snide comment nor meant to suggest doubtfulness. I thought his response was proper and thoughtful.

[Bob999]

 I also told him that Optima makes a supposedly more robust after market battery for the Prius. The Customer Care Manager responded to the second of these suggestions by saying that IF sufficient reports come in of battery problems related to the battery being too small in reserve capacity, then Ford potentially might design a more robust replacement battery that it might offer through a Customer Satisfaction Program. The highlighted words are there for accuracy's sake, not a snide comment nor meant to suggest doubtfulness. I thought his response was proper and thoughtful.

 What I find interesting is that the battery specification in the owners manual is for a more robust battery.  My car, and by several reports on this site other cars, came with a 390 CCA battery installed at time of delivery.  However, the specification for the battery in the manual is for a 500 or 590 CCA battery

[salman]

 What I find interesting is that the battery specification in the owners manual is for a more robust battery.  My car, and by several reports on this site other cars, came with a 390 CCA battery installed at time of delivery.  However, the specification for the battery in the manual is for a 500 or 590 CCA battery

 

Thanks for pointing this out. I have missed mention of this point in earlier postings or maybe for some reason it did not register with me. I will check my manual and check my 12 volt battery. I gather the CCA is listed on a label on the battery? Or did you need to look up the model number of the battery to check its specs?

[salman]

Here is a technical question for anyone out there who can offer an explanation:

 

I am not sure that CCA is the most important spec for C-Max battery. CCA is about the maximum output power of a battery. Since the C-Max doe snot need a lot of Amps to turn on (no starter to crank), my hunch is that RC, reserve capacity, might be the more pertinent spec. RC is the amount of time the battery can continue to deliver power.

 

Here is general FAQ on battery specs: http://www.autobatteries.com/faq/index.asp

 

The question remaining is what specs should a C-Max battery meet ( if indeed an under-capacity battery is the cause of our problems)?

 

Similar problems seem to haunt other hybrids, including the Prius and other Ford models

[Bob999]

Thanks for pointing this out. I have missed mention of this point in earlier postings or maybe for some reason it did not register with me. I will check my manual and check my 12 volt battery. I gather the CCA is listed on a label on the battery? Or did you need to look up the model number of the battery to check its specs?

The CCA is a part of the model number--the last three digits and is displayed on the battery.

 

My understanding is that CCA and reserve capacity are correlated--higher CCA generally relates to higher reserve capacity.

 

As a side note as a result of all the discussion about problems I decided to check the state of charge on my CMAX by checking the no load  voltage at the connection points in the engine compartment.  I should note I have had no problems and frankly I expected to find a fully charged battery.  

 

However what I found was ~ 12 volts--indicating a state of charge of about 50%.  I have put a Battery Tender on to provide a trickle charge (max 1 amp) and see if the reading increases to indicate a full charge.  I will report my findings after the Battery Tender indicates it has completed the charge.

Edited January 9, 2013 by Bob999

[salman]

The CCA is a part of the model number--the last three digits and is displayed on the battery.

 

My understanding is that CCA and reserve capacity are correlated--higher CCA generally relates to higher reserve capacity.

 

As a side note as a result of all the discussion about problems I decided to check the state of charge on my CMAX by checking the no load  voltage at the connection points in the engine compartment.  I should note I have had no problems and frankly I expected to find a fully charged battery.  

 

However what I found was ~ 12 volts--indicating a state of charge of about 50%.  I have put a Battery Tender on to provide a trickle charge (max 1 amp) and see if the reading increases to indicate a full charge.  I will report my findings after the Battery Tender indicates it has completed the charge.

 

Your experiment will be interesting. 

 

If the battery takes a full charge up to 12.6 volts, then I suppose it could be tested at intervals (12 hours, 24 hours, etc) to see at what rate it loses charge. Ford's tech people should have a range for proper discharge over time (all batteries discharge over time plus there is a small discharge to maintain the on board computer, etc). Anything above that would indicate a power draw that is not supposed to be happening.

 

Ford should be doing this sort of test.

Edited January 9, 2013 by salman

[CNCGeek]

I just checked my battery using the front jumping points, reads 12.36v now, after several days of driving with no problems since the first one.  I did notice while checking the voltage that the panel cover for the battery connections and fuses had been removed.  When I looked at it previously I guess it did not register that there should be a cover on the panel, or I just did not look well enough.  I know I did not remove it, so I am now suspect if they had some issues with this at the dealer.  They may have just charged it up though, or jumped it which is probably pretty common at dealers.

 

Edited January 9, 2013 by CNCGeek

[Bob999]

Here are the results of my charging experiment.

 

Recall that when I tested the no load voltage at the connections points in the engine compartment I got ~12V which indicated a state of charge  (SOC) of ~50%.

 

So I connected a Battery Tender overnight and this morning the Battery Tender had gone into the anti sulphating mode indicating it now detected full charge.  When I checked the voltage with the Battery Tender still connected and powered it was 12.7 v indicating full charge.

 

I then removed the Battery Tender and opened the driver side door briefly to put a very small load on the battery.  I then retested the voltage at it was 12.0 v!!!.  I also tested the voltage at the power port at the rear after opening the power liftgate and also got 12.0v.

 

I supose I should access the battery and measure the voltage at the battery terminals but haven't done that yet.

 

Overall I am puzzled by the results.

[salman]

Bob999

 

Very odd.

 

Did you take a reading after disconnecting the charger but before opening the door? 

 

If you replicate the findings in a 2nd test I'd think it would be interesting to bring the car to Ford and see what they say.

[Bob999]

Bob999

 

Very odd.

 

Did you take a reading after disconnecting the charger but before opening the door? 

No.  But I think I will put the Battery Tender back on and include that after the indication of a full charge.

[MikeB]

Very interesting observation, Bob.

 

Either your 12v battery won't hold a charge for any amount of time, or there's something between you and it that's holding the measured voltage down.

 

I've got a guess, wonder if I'm right. We know there's a DC/DC converter on board, taking power from the 300v big battery and turning it into something near 12v. I bet you're seeing the output voltage of a DC/DC converter, rather than the 12v battery. But the DC/DC converter really should be putting out about 13.9v, not 12v, in order to charge the 12v battery and provide full power to the headlights. If it's not putting out enough voltage, that might explain why the 12v battery isn't getting charged enough. 

 

I'd really like to see a basic wiring diagram for this car, at least for the main power flows. It's got to be more interesting that we are used to, by an order of magnitude.

[cgul]

My scangauge shows 14.8 volts with the car running and I just checked after sitting for about 5 hours in the garage 12.9 volts. I had to put the car in accessory mode for the scangauge to come on and the headlights and radio were on also but the engine was not running of course.

 

I just checked the voltage after about 20 hours and it checks 12.16 volts with my expensive DVM. The scangauge still reads 12.9 so I would say the scangauge voltage readings are about .7 volts high.   

Edited January 11, 2013 by cgul

[zhackwyatt]

Very interesting observation, Bob.

 

Either your 12v battery won't hold a charge for any amount of time, or there's something between you and it that's holding the measured voltage down.

 

I've got a guess, wonder if I'm right. We know there's a DC/DC converter on board, taking power from the 300v big battery and turning it into something near 12v. I bet you're seeing the output voltage of a DC/DC converter, rather than the 12v battery. But the DC/DC converter really should be putting out about 13.9v, not 12v, in order to charge the 12v battery and provide full power to the headlights. If it's not putting out enough voltage, that might explain why the 12v battery isn't getting charged enough. 

 

I'd really like to see a basic wiring diagram for this car, at least for the main power flows. It's got to be more interesting that we are used to, by an order of magnitude.

If the car isn't on, then the Hybrid battery is isolated from the system.

[Bob999]

I put the Battery Tender back on and this time it indicated full charge within about 2 hours.  With the Battery Tender connected the voltage was 12.7v.  After disconnecting the Battery Tender, but with no load of any sort the voltage still read 12.7v.  But after opening the driver door briefly--which does put a load on the battery while it is open--the voltage dropped to 12.0v.

 

I think I will try a very simple resistive load test tomorrow--The tester simple reads the voltage with a fixed resistive load and gives a good, fair, poor result based on the resulting voltage.

 

One other observation--I got a "normal" voltage at the 12v outlet by the cup holder in the front of the car.  This was after the car had been sitting for more than 24 hours and without putting the car in assessary mode or starting it.  I didn't expect to get a voltage there based on posts on this site indicating that outlet shut off after a short time after the can is shut down.

[salman]

Bob999

 

Just my cautious two cents, so take this with a grain of salt: If I were you, I'd bring the car into Ford before doing any more tests, especially load tests,  and tell them what you found. See if they can explain the drop from 12.7 to 12 volts just from opening the door.

 

I am assuming you opened the door and then shut it, and then put the meter on the battery. Did you wait long enough for all the lights, etc to go out? It might take a few minutes for all systems awakened by the opened door to shut down. 

[Bob999]

Bob999

 

Just my cautious two cents, so take this with a grain of salt: If I were you, I'd bring the car into Ford before doing any more tests, especially load tests,  and tell them what you found. See if they can explain the drop from 12.7 to 12 volts just from opening the door.

 

I am assuming you opened the door and then shut it, and then put the meter on the battery. Did you wait long enough for all the lights, etc to go out? It might take a few minutes for all systems awakened by the opened door to shut down. 

I got the 12.0v after shutting the door but probably before the lights inside the car were totally off.  I checked the voltage perhaps 30 minutes later and it registered 12.3v.  Not great and probably suggests the battery is a bit degraded but not enough, in my opinion, that it would be replaced.  So for now I am just going to occasionally check the voltage.  If I have another reason that I have to see the dealer I will raise the matter but other wise I will wait for a more definitive sign of a problem.

[CNCGeek]

One other observation--I got a "normal" voltage at the 12v outlet by the cup holder in the front of the car.  This was after the car had been sitting for more than 24 hours and without putting the car in assessary mode or starting it.  I didn't expect to get a voltage there based on posts on this site indicating that outlet shut off after a short time after the can is shut down.

 

I have also noticed this, it does not shut off.

[andrewwx]

Hi All:

 

Ford called me Thursday and told me that they believed it was the dealer installed alarm system was not compatible with the Cmax. They took the alarm out (refunded my money) and gave it back to me. I drove it all day Friday and all was good. When I went to use it Saturday morning it was dead. Very sad. I am going to drive it and hopefully it will die again when the service department it open and I will have them see it in its dead state (although I do not think it will help them diagnose the problem - just show them in its dead state)

 

What I am noticing is that sometimes when I open the door only the ambient lights and the center sync display light up. The main driving display is dark and only comes on when I hit the start button most of the time when I open the door the main driving display lights up. Sometimes only the speedometer lights up and the left and right side displays are dark. I think I read some other member had a short in his display.

 

I will call my service manager and Ford customer service tomorrow.

 

Cheers

[andrewwx]

Redldr1: Have you had any problems with your Cmax since they put a new display in?

 

Cheers from a rather chilly southern California

[salman]

Andrewwx

 

Thank you for the details and for keeping Ford central informed, too. Your case sounds like it might have great diagnostic value because of the repeat experience with a new battery and the alarm system.

 

I went back to look at your old posts to see the whole story: It looks like you already had a battery changed because it had a bad cell, but the dead battery issue continued, and now Ford decided (maybe correctly) that the dealer installed alarm system might have been the cause. So the alarm was taken out, but the battery is still dying. I noted, too, that you report what seems to be odd shut down and turn-on of cabin lights and instrumentation.

 

Here are two hunches I have, the first of which is pretty obvious and already on your radar::

 

1) There might be another electrical system problem that Ford has not yet tracked down.

 

2) The replacement battery might be damaged and it could be the case that the alarm system fried two batteries. While I do not think we can rule out other problems in the electrical system (shorts, drains, etc), I am beginning to wonder if the batteries are exceptionally prone to damage from being drained. If the batteries cannot work within an acceptable range of capacity after being drained down once when the batteries are months old, then these are really weak and insufficient batteries in need of replacement with better models.

 

Ford has to be able to explain why the problem has come back. 

[andrewwx]

Hi All:

 

Thanks salman. My service guy did say that the new battery was good. Its a bummer the forum rules wont let me send a msg to Redldr1 until I accumulate enough posts, but it would be interesting to find out if the new dash assembly cured his Cmax.

 

So after my 10 hour graveyard shift the Cmax was again completely dark. I called Ford roadside assistance and waited an hour. the tow truck showed up and informed me that he had to jump the car because I did not park nose out. Just not my day. I drove the car to Ford and handed it off. The Service manager is rather baffled - I told him about my dash light observation. I have a rental car again. People at work are giving me the ol' Fix Or Repair Daily jokes now. I hope they find out something.

 

Cheers

 

Andrew

[salman]

Andrew

 

Here is a thought: Ask the Ford service tech how he tested the battery. Did he just test for voltage charge? Can he test whether the Reserve Capacity (RC) has been damaged? I do not know whether or how that can be tested, but I am pretty sure that a battery can charge to the proper volateg level but not have the RC it is supposed to have. The RC is a measure that helps to determine a battery's ability to supply power over time.

 

If the tech keeps saying the battery is good, then he (and Ford) has to admit that there is another problem (even if he cannot yet identify the problem).

 

Either way, make sure the tech is on the phone with Ford's Hotline for service techs. The dealership will know the Hotline phone number.