Audio fails, then vehicle won't start--jump resolves temporarily, until problem recurs

[hbabbcook]

Apologies for yet another post about a dead cmax...

 

I have a 2013 Ford C-Max Hybrid only vehicle. In the two years I've owned it, it has been unable to start unassisted 6 times, leading to significant tow and repair costs. So far, nobody has been able to fix the problem. The very first time they found a loose relay in the trunk, and the 3rd time they replaced the battery, but five different shops including two dealerships have run diagnostics and been unable to find the problem causing this.

 

The last three times have gone the exact same way. All in the last 6 months, with a less than 1 year old battery. First, the audio stops working--won't turn on or off with the power button, can't play radio or connect to a phone. Screen lights up and the navigation/menu system still works fine. Then, about two days later, the car will be dead. Won't unlock with the remote, no dome lights, nothing. Twice we have jumped it, and that completely fixes it--still took it to a shop each time, but it turns on and off like a champ and shows no other symptoms/no signs of battery draw.

 

The most recent time we didn't even try to jump it and had it towed in dead so they could at least see we weren't making stuff up. Dealership had it for a week, didn't find any problems or offer any explanation. Just charged us for labor and diagnostics and sent us on our way.

 

Anyone have any experience with these problems? I'm open to all options--preventatives, maintenance, work arounds, fixes, literally anything. I can't accept that I have a 6 year old car that won't start without a jump every 4 months. Any help is much appreciated!

[plus 3 golfer]

Many have / have had similar issues especially with early MYs. Did the dealer make sure all TSBs and CSPs have been done on your car especially those relating to the "no start" issue? I don't have the info at hand but will look it up or others may chime in.

TSB 150089. CSP 15B04

https://static.nhtsa.gov/odi/tsbs/2015/SB-10058325-1132.pdf

https://ford.oemdtc.com/1696/15b04-12-volt-battery-test-and-module-software-update-2013-2014-ford-c-max

 

1) When the radio stops working try pulling fuse 79 under the glove box and reinsert. You may need needle nose pliers or fuse puller. This should reset several control modules. I assume radio doesn't work on restart. So, it's likely the radio / associated modules are draining the 12 V battery in the next two days so then the car won't start.

 

2) Next time you drive. Leave radio on. Stay in car and turn car off via pushbutton / key. Time how long the radio stays on before the message comes up on the display saying something like "Shutting down to conserve power." Depending on when you had the battery replaced, the time could be as long as 10 minutes.

 

3) Get yourself a portable jump start battery so you can jump the car from under the hood and carry in car in case issue crops up away from home. The control modules need to have a good 12 V battery to operate. The cars engine does not have a typical starting system. It uses the High Voltage Battery to run the generator motor in the transmission to start the engine. The control modules must close the contactors to the HVB. Once closed, the DC-DC converter supplies power to the 12 V system. There is no alternator as in a conventional vehicle.

Edited February 26, 2019 by Plus 3 Golfer

[SnowStorm]

As mentioned, make sure car is up to date on TSBs, especially 14-0155 which addressed dead 12V batteries.  (See this topic and read the TSB.)  I had several dead batteries (and I mean dead) but have had no problems now for years after having 14-0155 done.  I don't know how you find out if its been done.  Find a dealer that has performed this TSB - maybe they can tell you.  If not, I'd have them do it anyway.  You might have to pay for it now as I recall there was a cutoff date for getting it done for free.  I had it done at the "11th hour" and my battery failed the test so I got a new one free.

Edited February 26, 2019 by SnowStorm

[homestead]

Once the car is up to date on TSB's & sync version and

 the radio locks up again, pull the fuse(s) to fix that problem right away.  If you don't it may leave the car electronics in a state

where the battery will be drained.

[smcguire]

WORKAROUND:

 

When I first got my 2013 C-Max Hybrid, in the summer of 2015, the 12v system would regularly go dead, which was annoying as hell.

As others have mentioned, bringing it to the dealer to have some TSB updates applied solved the problem, but in the meantime, I found a good workaround which I recommend to you.

I went to Wal-Mart and bought a booster pack... which is basically a motorcycle battery in a plastic case, with built in booster cables.  It charges from 110 volts, so I left it in my car, plugged into the electrical outlet.  That meant that it was charging all the time the car was running, and any time the 12v system was dead, I could just pop the hood and hook that up to bring my c-max back to life.

In a perfect world I wouldn't have had to do it in the first place, but the first time it saved me needing to get help to boost my car it was well worth the $125 or so that the booster pack cost me.