Ford Fiesta parasitic draw on battery??

crash7

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Crash7
My daughter has a 2014 Ford Fiesta. Got it 1 year ago and it had a new battery put on at that time. In the last month, it has been dead three times when she goes to start it. She generally drives every day, but each of these times the car did sit for 2-3 days.

I'm having a shop look at it now, but so far he says the battery is ok and he's only showing 30mA draw when "asleep", which I think falls into the normal category. So, it looks like an intermittent issue (of course).

Anyone out there in TV land have an intermittent issue like this? What were the typical culprits?

Thanks in advance!
 
A temporary fix is to get a battery disconnect switch which goes on the battery and you turn a knob to reconnect the battery before use. I did that once on an old Corvette that did the same thing. I never trust battery tests done by anyone except me. Was it a load test or did they just look at residual voltage. I like to test my batteries with these: https://www.amazon.com/gp/product/B08K3885C4/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 They do a calculation of cranking amps or cold cranking amps and then compare with CA or CCA stamped on the battery. Also check for dome lights left on, trunk lights that do not shut off, glove box lights that do not go out when the door is shut. Sometimes the USB ports do not shut off when the ignition switch is off, check for anything that might be plugged into that.
 
My wife had a 2012 Focus. I like Fords but the Focus and Fiesta are an electrical nightmare waiting to happen. We gave the car to my daughter (parent's revenge). My suggestion is to have a look at the GEM (sometimes referred to as the BCM). Can't say this is the problem but it's a place to start.

https://moduleexperts.com/gem-modules/
 
What were the typical culprits?
There are several. Is the alternator/charging system to spec? If not then the battery is consumed each time driven, then when parked for 2-3 days the 30mA drain might kill the rest. That said, the 30mA drain when off is typical on a "modern" vehicle but with some of the newer models it can be closer to 90mA. And since you drove the car to the shop you may have "reset" the culprit. If the charging system checks out good and you want to continue troubleshooting an intermittent problem, monitor the voltage when driving by either the vehicle indicator or a plug variety. Another check when you go to park it for 2 days is check to see if the 30mA drain changes during the 2-3 days. That's where I think it is. If that drain rises to 200mA or above then that maybe enough to zap the battery especially if it has been severely discharged in the past.
 
I’ve put a volt meter on it while it’s running and see 14 volts. I’m no electrician, but that’s right for the alternator, correct?

If I randomly go out at try to check the amp draw, wouldn’t I alter the scenario simply by unlocking the car, opening the door to be able to pop the hood?

I hate intermittent things. I haven’t heard back from shop today. Guess it’ll be tomorrow.


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I’ve put a volt meter on it while it’s running and see 14 volts. I’m no electrician, but that’s right for the alternator, correct?
Yes. Anywhere from about 13.5v to 14.5v is good. Provided it charges at that rate the entire time you're driving. Did the shop also load test your battery. Regardless if its a year old if it was heavily discharged to below 10.5v it could have damaged the plates which has reduced its amp-hour capacity. The load test will determine that.
If I randomly go out at try to check the amp draw, wouldn’t I alter the scenario simply by unlocking the car, opening the door to be able to pop the hood?
It's possible depending whatever is behind the drain. But I'd give it a try. Just don't start the car as that will put the computer and other systems into a different loop. Another option is to park the car then rig up a parasitic drain test harness that you can access from the exterior.
I hate intermittent things.
Me too. And especially electrical ones. Thankfully most aircraft ones are much easier unless the aircraft has computers as well.
 
You're probably already doing this, but make sure to check for that 13.8 or 14 v or so across the battery terminals, at idle. Weak alternator, bad terminals to the battery, and it may not charge at idle. Second thing is that a battery typically only lasts 3-5 years, from my experience, and if it's ever been let go to 12.0v or less, not as long.

As to the problem, could be stuck relay somewhere, aftermarket remote starter or stereo, bad light switch that's leaving a dome or trunk light on or something.
 
As to the problem, could be stuck relay somewhere, aftermarket remote starter or stereo, bad light switch that's leaving a dome or trunk light on or something.

See my post #3 above as that module is the controller for the multiple relays in the vehicle. One method I've used on older vehicles is to set up a meter in the system to read the parasitic draw and then remove fuses/relays one at a time until I found which circuit was causing the fault. In the newer vehicles with a GEM that method goes out the window and I'm guessing only the dealer will have the proper tools and needed schematic to find the problem.

Of course it could be as simple as a faulty battery ...
 
If you understand how to use a volt/amp meter go to the youtube channel below and find videos where this guy troubleshoots battery drain issues. He's methodical and shows the methods he uses to figure out what is causing the issue.

South Main Auto Repair LLC - YouTube


Here is one of the videos where he shows how he solves a battery discharge issue.


And another, he does a few of them.

 
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You have to be careful about pulling fuses these days. You can trigger other modules to not go into sleep mode and then pull more power than usual.

A couple of things to try.... pull the dome light, trunk light, glove compartment one and the under hood one. All are known culprits for oddball battery drains.
 
Might be a different situation, however the same thing was happening to my wife's car in the winter. She would drive to work a couple of miles each day with heater fan full blast, heated seats on, defogger on, radio no. Never had a chance to charge the battery over a few days period. Fix was to go rotate the vehicle with mine so we could even out the average mileage and give it a chance to charge on my longer commute.
 
I’ve watched a ton of those videos. Thing is the shop I took it too said he didn’t see a large amp draw to even investigate. That’s the annoying intermittent part.

I’ll talk to him today and see if anything happened overnight. If not, I may just get a new battery and see what that does for now.


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If she is keeping the keys in the ignition while parked at home that might be the issue. Also see if she has USB ports plugged into the 12 volt sockets. Some 12 volt sockets are always hot and cheap USB adapters can generate a draw.
 
If she is keeping the keys in the ignition while parked at home that might be the issue. Also see if she has USB ports plugged into the 12 volt sockets. Some 12 volt sockets are always hot and cheap USB adapters can generate a draw.

Keys are not kept in car. We have 2 fobs. She -did- have a usb plug in the cigarette lighter for charging her phone, but I made her take it out last week. A few days later it still went dead.

This car has an add-on remote start. I’ve heard iffy things about those. I wonder if having the mechanic disconnect that would help...


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I’ve watched a ton of those videos. Thing is the shop I took it too said he didn’t see a large amp draw to even investigate. That’s the annoying intermittent part.

I’ll talk to him today and see if anything happened overnight. If not, I may just get a new battery and see what that does for now.


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The problem with shops is it takes a good technician to do what the guy in the videos I posted does. It's not rocket science, but it is above the level of most people to troubleshoot this stuff. I hope your shop figures it out, because if not you will have a frustrating experience.

I trust they have checked the obvious, like done a load test on the battery, and made sure the connections are clean.
 
How timely. I just replaced the battery in my truck because it would go dead overnight. One think I didn't do when I replaced the battery a year ago was reset the computer (on mine it was flash the headlights to bright 5 times and the brake 3 times - after 5 seconds a battery symbol flashes three times confirming that the computer was reset to let the truck know a new battery was installed) I still think I have a parasitic drain somewhere but I'm going to take it to someone who has the equipment like the guy in the videos above to find it.
 
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My local guy couldn’t find anything wrong. Swears the battery is ok.

The shop that installed the radio last February is looking at it now.

A dealer said they wouldn’t be able to do much more than what the local guy did. Grrrr.

If radio shop doesn’t find anything I guess I’ll just blindly replace the battery and see what happens.

Anyone want to buy a car?


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I’ve watched a ton of those videos. Thing is the shop I took it too said he didn’t see a large amp draw to even investigate. That’s the annoying intermittent part.

Finding these problems oftentimes takes equal parts of patience and luck. What is likely happening is that one of the modules isn’t “going to sleep” when sitting idle for a longer period of time. Your guy may not have seen it happen because it worked ok when he was looking at it or he didn’t wait long enough to have everything go into a power conservation mode.

Having aftermarket electronic components on the car can potentially make things more challenging. I’d disconnect the remote start and any interface module associated with it to start and see what happens.
 
Interesting... the place that put the radio in says they see some sort of draw in there. They asked if I still had the original radio (to help troubleshoot something). Heh, no. That went in the trash.

They’re still looking...


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I believe it was the Fiesta for which the Car Guys said the funeral wreath was optional.
 
How is she driving the car?
A few short trips won’t charge the battery.
I’ve seen this a few times, even starting to use the electric rear window defrost for the winter will make the car have to drive further to charge the battery.
Happens more on small/ low cost cars with small alternators.
You’ve checked everything else. 14V at charge. 30mA draw is fine and I’d trust a mechanic if they say the battery is ok.
The only other thing would be to check battery voltage 1 hour after shutoff and again the next morning. 12.6V is fully charged, 12.1V is 50%.
Good luck.
 
A Ford with an electrical problem? Say it isn't so! ;)

I have had several Fords over the years. They like their electrical gremlins.
 
Are the key fobs kept close enough to the car that they are “talking” to each other?
 
The radio shop found a 90mA draw in there somewhere (not sure why the first mechanic didn’t see that). They bypassed something that was part of their install and the draw went to .9mA.

Covered under warranty. We’ll see how it behaves for next next few days.


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The radio shop found a 90mA draw in there somewhere
You may want to get a 2nd opinion on your battery load test if the shop missed a 90mA drain. That still shouldn't drain your average car battery in 2 days unless the battery is hurt.
 
My daughters Buick had a bad BCM that was turning on the internal lights and other things, thus draining the battery every night or while she was at work for 8 hours.
 
You could always just wire a big relay for everything but the starter. Phantom power is a PITA that wouldn't be needed if the system designers weren't lazy or too cheap.
 
If that doesn’t solve it, I’d really look at the remote start. I’ve heard a lot about those having various issues (aftermarket, not factory). Further, installing one is not a picnic and accesses a lot of wiring in the vehicle as I recall (been awhile since I looked at one).
 
Probably gonna jinx it, but since the radio shop changed something we haven’t had the issue. Granted it hasn’t sat for more than 2 days, but we’ll keep an eye on it.


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You could easily fix the problem yourself for a couple of bucks using one of these: :dunno:
iu
 
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