Long of the short, my partner owns a 2012 Ford Fiesta - WT 1.6L 6SPA ZETEC HATCH which is ~95,000kms on it. We are in Australia.
Last night the car would not start, and she was luckily able to get a jump from a nearby mechanic. The mechanic advised that the battery was old and needed to be replaced, though couldn’t do it then and there.
She drove it home, and advised the car was sluggish with an error code.
I look at the car this morning, and whilst it started on the first attempt, I noticed a ‘Transmission Malfunction’ error on the dash. I was able to reset the code (key to on, car in neutral whilst the transmission message displays).
A google search suggests that it might be more than just the battery, possible a ‘TCM’ issue (Powershift error or something along those lines).
There were various posts about extended warranties on the transmission, class action lawsuits, dealerships replacing it for free etc, though most seem outdated or not applicable to Aus.
Anyone have any guidance on what to do? We may get the battery replaced just to give it some life - she doesn’t drive very far luckily. Though if it’s an underlying issue, like the TCM issue, what can we do - is it possible to replace, will Ford still adhere to their warranty (noting very low Kms) etc?
Hi everyone, thanks for your comments! The battery has been replaced, but the message is still showing, even after the neutral reset. I’m not sure if that actually clears the code since the internet suggests it might not. I’ll have my partner drive slowly (the speed limits around us are 40/50 km/h anyway) and see if that helps. I also have an OBD2 tool I can use to clear the code if needed.
Fingers crossed it’s just a battery issue and not the TCM.
Just another update in case it helps someone else! After replacing the battery, the error still showed up even after driving for a while. Thankfully, I had an OBD tool, and I was able to clear that specific code. It’s been three days now, and the car drives like a dream—no issues at all!
The transmission can’t function properly without a good battery, so that’s where you should start. Also, make sure the alternator is in good shape, as a bad battery can damage it too. It’s probably just fine! In the USA, a battery for that car costs around $60 and takes just three minutes to replace. Driving with a bad battery can cause further damage. Some updates to the TCM were designed to disable the car if there’s not enough power to operate the transmission clutches, preventing it from ruining itself.
Hey! I had the same situation when my battery died. First things first, definitely replace the battery, and then take it somewhere to have both the battery and alternator tested. In the USA, you can do this at auto parts stores like AutoZone or O’Reilly, but I’m not sure about other countries.
If those test okay, the next step is to clean the paint off the ground connection. This is the black “negative” cable that connects from the battery to a metal contact point. If you see any paint where this cable attaches to the car’s body (about five inches away, so it’s not hard to find), disconnect the cable using a 10mm wrench (it’s just two bolts—pretty easy). Then scrub it hard with sandpaper or even steel wool to get it down to bare metal. This will improve the connection between the battery and everything else, which is a fix Ford implemented in a recent recall.
After that, it’s a waiting game. It might take days or even months, but the TCM will eventually reprogram itself. You can speed things up by disconnecting the battery overnight or following the TCM reprogramming procedure. There are YouTube videos that explain this, but I remember it involves turning the key halfway and putting the car in neutral for about 10 seconds—definitely look it up for the specifics. Do both and just wait; one day, you’ll hop in, and it’ll magically work again.
If that doesn’t work or you can’t wait, you’ll need a new TCM. These can take over a year to get from Ford, so you might have to settle for a cheap aftermarket one. They can be tough to find, but you might have luck on eBay or other auto websites. Make sure to call an auto shop to see if they can program the TCM, as it requires specific computer software that only some mechanics have.
The issue occurs because when the battery is low, it cuts power to various parts of the car, eventually affecting the Transmission Control Module (TCM). This can trigger an error message once power is restored. Usually, replacing the battery and clearing the code should resolve it. Unless you’re hearing strange noises or experiencing rough shifting, it’s likely just the loss of power that caused the transmission to enter limp mode to protect itself.