Hello,

Got a 2012 Mustang (manual transmission) that I recently acquired with 111,654 miles.

drove it for a couple weeks and it sat in the garage for a week, when I turned the key it wouldn’t start.

got my Noco power jump pack out and connected it, when I turned the key the engine cranked on. However the dashboard turned on for a few seconds , then began to blink all of the lights. The radio screen turned on to default settings.

powered off the engine. Tried it again.

same thing, dash board lights blinking like crazy. shows “—- miles to empty” and switches between other screens while the check engine light, and other sensor lights are flashing constantly. And this time, the radio screen did not power on, no A/C, only the dashboard kept blinking. I powered off the engine and let the car sit. I had to get a ride, for fear of the engine/car turnkng off on me mid-ride.

any help please?

is this the result of a dead dead battery? Or maybe an issue with the ECU?

please help. I’m new to the Mustang world. Will post a video soon..

 

I would have one of the auto stores check the strength of your battery first. I've had that same issue with my DD's but not with my pony. It was a bad battery and once replaced all was good. So hopefully this is where it starts and ends for you.

 

Yeah, hopefully just a bad battery .... give it a really good charge and/or have it tested at an auto parts place. But be aware, I have had batteries fully load tested by Advance Auto and the battery showed good, but it actually was not. I was having trouble with the battery holding a charge, and when I replaced the battery, the problem went away (even though the battery had tested "good")

or you can check it yourself: give it a good charge (using a good charger), take it off the charger, then check the voltage across the terminals. It should be a little under 13 volts. Let it sit and check it again several hours later. If the voltage has dropped, you need a new battery.

 

Check Battery For Date Code If It's Over 3 Years I Would Get a New One Regardless!

Make Sure Your Cables Are Clean Clean Clean!

KC

 

Also, have your alternator tested along with the battery... Knowing your vehicle has over 111k miles, its very possible your alternator may need replaced, especially if its original from the factory...

 

so I charged up my battery with - a Noco 5A charger to 100% , started jt up but now it’s still having the same issue.

 

so I charged up my battery with - a Noco 5A charger to 100% , started jt up but now it’s still having the same issue.
I wonder if it is the alternator causing this issue? I’m posting a video of the issue now. Please help

 

so I charged up my battery with - a Noco 5A charger to 100% , started jt up but now it’s still having the same issue.

checking the battery date now, it says 3/24, it’s practically a new battery only 5 months old.. someone on here replied saying it could be the alternator?

any other suggestions? 😢

 

let me try this out. so I charged up my battery with - a Noco 5A charger to 100% , started jt up but now it’s still having the same issue.

I will test the battery voltage again soon. Maybe it’s a completely dead battery or a bad battery. Someone on here said it could be the alternator. Hmm. Any suggestions?

 

Need To Check For DTC & Body Codes! So A Good Scanner is A Must. As With All S-197's A Water Intrusion on The Sjb Can Cause a Lot of Issues As Well! A Peak Under The Cowl Might Be a Good Idea! Checking The Sjb as Well For Signs of Water Intrusion Would Be Good Peace of Mind To Avoid Future Issues!

https://themustangsource.com/forums/...on-sjb-550481/

KC

 

not sure what's up with all the repeated replies ...

scanning for codes is always a good first step

yeah need to test the battery, they can look like they are charging fine, and start the car no problem immediately after charging, but still not maintain proper voltage -- this might not be the issue but needs to be eliminated as potential cause

and do get the alternator tested also -- again that might not be the issue, but before you move on to more difficult things, it's good to eliminate it as possible cause

also check for wetness on the passenger floor, clogged cowl drains (located on the firewall, one on each side) -- this would suggest you should look harder at the SJB (like he ^ said) which is located in the passenger kick well area

 

I just wanted to chime in for the OP. Yes, new batteries can be bad, especially 'mongrel' brands. Sounds like it's time for a trip to your favorite mechanic if you can't do things yourself. I sure can't and that's where I would head to see what's going on. A new alternator and new battery would hopefully be the worse case scenario unless the wetness problem or loose cables. Good luck!

 

I was the one who suggested having your alternator tested... It's also unnecessary to submit duplicate posts!!!!