Hello,

I have a 2017 Fiesta. In the past few weeks I had a warning on my dashboard telling me that I needed to change the battery in my key. This was showing up for both keys. Me being as silly as I am, I decided to put this off until the last minute (when I realised that both of my keys were not working). At first, the car's indicators would blink once when I pressed a button, but any subsequent presses would not do anything. I even set off the car alarm when I double-pressed the boot unlock button. But soon after, the keys were not doing anything at all.

I ordered some CR2032 3V lithium coin batteries and replaced the old batteries in both keys. I tried each key and they are still not working. I'm not quite sure what the cause could be. I hope you can give me some suggestions for what I should do.

Firstly don't assume that the new CR2032 batteries are working, there are many counterfeit and poor quality batteries on sale. You need to use a digital multimeter and measure the voltage of the new batteries, they need to be 3.30V. If they are less than 2.99V then they are dead.

It may sound a silly thing to suggest, but are you 100% sure that the batteries are the correct way up ?

If you are using Duracell (not recommended) clean the batteries with IPA, acetone, or nail polish remover as they have an invisible coating on them which causes poor electrical contact.

I've bought CR2032 batteries which have a thin clear plastic disc stuck on one side which has to be peeled off before fitting the batteries. I just thought it was worth a mention.

 

I put a Tesco Cr2032 in my key fob - it lasted 3 weeks...

Someone on here recommended Energizer so changed to them and they are working fine.

 

14 hours ago, Matt Alsop said:

I've bought CR2032 batteries which have a thin clear plastic disc stuck on one side which has to be peeled off before fitting the batteries. I just thought it was worth a mention.

 

Yes, that disc or other sticker (some brands have a warning about the risk of swallowing the cell) can leave a virtually invisible residue so need to be thoroughly cleaned off before fitting as Unofix mentions above. I use meths (for cleaning!)

 

11 hours ago, Tiexen said:

I put a Tesco Cr2032 in my key fob - it lasted 3 weeks....

 

I've had a similar experience with Duracells (or were they?)

I always stick with Panasonic personally. We use them at work with motherboards, and systems.

Although as with any battery, there will be fakes out there and ones that have been sat around too long. Make sure it's fresh and genuine.

I'm a fan of Panasonic as well.  Have now had 3 sets from this seller for different cars, all worked flawlessly and had a long date despite the low price!

Panasonic CR2032 3V Lithium Coin Cell 1 Card of 2 Cells 5009876566431 | eBay

Panasonic coin batteries don't have any bitter coating, do they?

You know, I had initially ordered Procell batteries, which I ordered in a bit of a hurry, it was only after that I realised they were industrial-grade batteries and since they are a part of Duracell, I assume they have the same bitter coating on them that could be making them non-functional. If they do have that coating and if it is the reason they are not working, I don't know if I have any suitable product around to remove it, unless there's some more crude way of doing it.

10 minutes ago, fiesta2020 said:

Panasonic coin batteries don't have any bitter coating, do they?

No.

1 hour ago, fiesta2020 said:

...I don't know if I have any suitable product around to remove it, unless there's some more crude way of doing it.

Go into her make up drawer and grab some nail polish remover!

I prefer energizer

4 hours ago, fiesta2020 said:

Panasonic coin batteries don't have any bitter coating, do they?

You know, I had initially ordered Procell batteries, which I ordered in a bit of a hurry, it was only after that I realised they were industrial-grade batteries and since they are a part of Duracell, I assume they have the same bitter coating on them that could be making them non-functional. If they do have that coating and if it is the reason they are not working, I don't know if I have any suitable product around to remove it, unless there's some more crude way of doing it.

Have you checked the battery voltage with a multimeter ?

Interesting factoid arguably…  My dad used to test cheap brand batteries by literally setting the Multimeter to Amps (10 Amp range for the likes of AA/AAA) and seeing what they read as a gauge to their amp hour capability.  Obviously you didn’t want to do it for more than a second, otherwise the battery would be screwed very quickly as the meter is almost a dead short on this range.

However, what came to light was that some dodgy branded AA’s would dish up almost as many Ah’s as that era’s Duracell’s (used to be the benchmark in the olden days) and for about half the price.  I’ve continued this tradition to this day and reaped the benefits.  However, I’ve had pretender alkaline batteries that have had great capacity for the price, but have corroded big style really fast before now.  FYI – Ikea batteries not bad, Halfords have good capacity but are fast rotters.

NB - if you try this, make sure the meter will test up to the Amps required.  For the above e.g. AAA cells, you’re talking about 4.5A.  Don’t try this on the car’s main battery!!!!!

2 hours ago, Marineboy said:

Obviously you didn’t want to do it for more than a second, otherwise the battery would be screwed very quickly as the meter is almost a dead short on this range.

Just a word of caution: Don't try this with any lithium battery (eg. CR2032) as short-circuiting the cell can very quickly cause a run away chain reaction and the cell may burst in to flames even a few minutes after the 'test' has been removed.

Lithiums don't like being shorted, well, that's something I didn't know as I've never tried it.  Good advice Uno.

You can relearn/pair the key/s. Key in, turn to first position and press lock a few times

sounds like you need to reprogram them.. theres videos on youtube 🙂

Wonder why the OP has abandoned us. He's a fellow countryman, and we usually have lots to say 😂

33 minutes ago, StephenFord said:

Wonder why the OP has abandoned us. He's a fellow countryman, and we usually have lots to say 😂

I'm here now lol. Anyway I managed to get into the car manually using the emergency blade hidden inside the key, but nothing happened at all when I placed the key into the "backup position", put the clutch down and pressed the start button. Although in the manual I realised after that it says this:

If the engine does not crank after you fully press the clutch pedal and press the push button ignition switch, do the following (with the passive key in the backup position):

1. Fully press the clutch pedal and the brake pedal.
2. Press the push button ignition switch.

So I will try that and see if I have any luck, as like I said the last time I tried I basically got no response whatsoever, to be honest I don't even know if the key was recognised even with it being in the backup position

Well, at this point I am going to guess it's just a flat battery. You know, while I was out at my car, I was expecting to hear the car alarm go off like it did last time I manually entered using the hidden key blade. But this time, I didn't. But I did hear something coming from inside the car, almost like some mechanism moving, with a regularity to it. Could that have been the car alarm trying to sound itself, but not having enough power to actually do so? Honestly would have no idea otherwise.

Does anything at all happen in the car?  Dash lights or Sync screen etc?

The noise could be the steering lock solenoid.

19 minutes ago, TomsFocus said:

Does anything at all happen in the car?  Dash lights or Sync screen etc?

The noise could be the steering lock solenoid.

Nothing came on, not the dashboard nor the infotainment screen. I think I saw the temperature dials light up for a second maybe but they quickly went back off again. The mirrors also did not automatically pop out after unlocking.

Your fellow countryman @StephenFord will be able to recommend a good battery charger and how to connect it 👍

5 minutes ago, unofix said:

Your fellow fellow countryman @StephenFord will be able to recommend a good battery charger and how to connect it 👍

On that note, I did find this one, thoughts? https://www.halfords.com/motoring/battery-maintenance/jump-starters/noco-gb40-1000a-jump-starter-721898.html?stockInventory=undefined

In the name of G*D !!!! How much ?????????????? 🤣

You just need a regular Smart battery charger

https://www.amazon.co.uk/Maypole-7423A-Battery-Charger-Electronic/dp/B009A83P1E/ref=sr_1_5?crid=3AQH0HFA2SCI1&keywords=maypole+charger&qid=1686427990&quartzVehicle=29-10519&replacementKeywords=maypole&sprefix=%2Caps%2C290&sr=8-5

as recommended by many of us here on the forum including myself.