[MartinC82]

At the start of 2019 my 2012 i40 Tourer blew the 15A Centre Console / Media fuse. I replaced this and all was well, however during the year the fuse would blow every now and again, until it now always blows. Initially I could turn the ignition between off and position 1 and the media unit would happily turn on and off, but each time the engine is started the fuse would blow. Now the fuse trips if the ignition is moved from position 1 to off or when starting the engine.

My first thought was a broken or bare wire, but after having a look at the back of the media unit during lockdown there is nothing obvious….unless it’s in one of the looms behind the dash.

Post lockdown I booked the car into my local Hyundai garage for some investigation and one thing that came back was the “battery wasn’t holding charge” and should be replaced. According to Hyundai, this can cause the media fuse to blow (never heard of that before?). The battery has now been replaced, however it hasn’t fixed the fuse issue.

Has anyone else had a similar problem?

Also any other ideas of what I can try to resolve the problem.

 

[AUTOSPARK]

one thing that came back was the “battery wasn’t holding charge” and should be replaced. According to Hyundai, this can cause the media fuse to blow (never heard of that before?).

No, I've never heard of that before either, and I've been an auto electrician for 30+ years. Some of these dealership techs just make $hit up as they go.

Sorry, I don't know what is causing the fuse to blow. These types of fault can be a bit tricky to diagnose, especially over the internet. But on the bright side, if the fuse is now blowing every time the ignition is switched on diagnosing the cause has just gotten a lot simpler. Intermittent shorts are extremely tricky to track down.

Is there anything else not working when the fuse is blown? Quite often the accessory fuse also supplies power to the electric door mirror adjusters. It would be worth checking to see if those work when the fuse is blown. The harness leading into the driver's door is a common place for short circuits to develop because the wiring between the car body and the door is flexed every time you open/close the door.

If I helped you fix it, why not...

Your support is greatly appreciated​

 

[MartinC82]

Thanks for the reply @AUTOSPARK, working in the electrical industry I was confused by the battery reason and I know far too well how difficult intermittent faults are to resolve! As you say the fact it blows all the time is a positive.

As far as I've noticed everything else is working correctly, the door mirrors certainly still fold in and move correctly, but I'll double check everything again tonight.

 

[MartinC82]

I now believe the problem lies in the Media Unit itself. Over the weekend I removed and disconnected the unit from the dash. I could then turn the ignition on and off and turn over the engine without the blowing the fuse.

Next task is to try and source a replacement.

 

[luckybricklayer]

I now believe the problem lies in the Media Unit itself. Over the weekend I removed and disconnected the unit from the dash. I could then turn the ignition on and off and turn over the engine without the blowing the fuse.

Next task is to try and source a replacement.

Hey, I have exactly the same problem. Media Unit blows the fuse only during the ignition, never when I'm driving. Have you solved your issue? Do you know which exact part of the Media Unit causes the problem?

 

[MartinC82]

Morning @luckybricklayer

Unfortuneately, I've not got to the bottom if the fault yet, mainly because some kitchen DIY and house selling got in the way!

I have a couple of local Hyundai garages and I contacted both about the issue, however neither gave the courtesy of a reply, let alone any information as to the cause of the fault

Have you tried anything to identify the fault?

 

[JedExodus]

Is there a fuse directly on the head unit itself? Some radios have one. If there is could be worth changing it out

 

[MartinC82]

Is there a fuse directly on the head unit itself? Some radios have one. If there is could be worth changing it out

Thanks for the suggestion @JedExodus, I'll check the head unit itself when I get a free weekend to remove it again. I wondered if there was some kind of protection relay or switch that wasn't going off when the ignition is turned on?

 

[JedExodus]

Thanks for the suggestion @JedExodus, I'll check the head unit itself when I get a free weekend to remove it again. I wondered if there was some kind of protection relay or switch that wasn't going off when the ignition is turned on?

Having a look at some units on ebay there doesn't seem to be a fuse. Or if there is it will require stripping the unit down to get to. If you're removing the head unit I'd check the wiring loom to make sure none of it is damaged. An exposed wire touching metal could cause the fuse to blow alright. Also have a look at the connectors and pins on the loom and on the radio. Have a look for corrosion. Wouldn't do any harm to give them a blast with electrical contact cleaner

 

[luckybricklayer]

Have you tried anything to identify the fault?

In my case, the fuse blows only during the engine start but not every time. For example, when I press the ignition button from OFF to ACC without starting the motor, the fuse does not blow, and the radio works correctly. After that, I can press the button once again to start the motor, and the fuse stays fine. Then I can turn on and off the radio and everything works well.
But when I start the motor by the first attempt the fuse immediately blows. For me, it looks more like the cause can be other than the radio itself. Maybe something else generates some huge temporary load during the ignition, and when it will sum up with the load generated by the radio it blows the fuse.

 

[luckybricklayer]

I've found a similar topic, but unfortunately, the author didn't share the solution

SOLVED: I have a 2012 Hyundai i40, multimedia fuse blew, - Fixya

I have a 2012 Hyundai i40, multimedia fuse blew, changed fuse worked fine until I started ignition then, fuse blew - Hyundai Cars & Trucks question

www.fixya.com

 

[luckybricklayer]

Hello @MartinC82 could you please tell me what exact model of battery you have now in your car? My mechanic told me that cars whith start/stop system require a specific kind of battery. Installing a common one can cause multiple electric malfunctions. I know that my battery does not support start/stop system

 

[telboy007]

Having a look at some units on ebay there doesn't seem to be a fuse. Or if there is it will require stripping the unit down to get to. If you're removing the head unit I'd check the wiring loom to make sure none of it is damaged. An exposed wire touching metal could cause the fuse to blow alright. Also have a look at the connectors and pins on the loom and on the radio. Have a look for corrosion. Wouldn't do any harm to give them a blast with electrical contact cleaner

 

[telboy007]

Hi guys any luck with the outcome?? I have exactly the same problem. All works OK but blows fuse as soon as the engine is turned on TIA.

 

[Zanzie]

Morning, my 2012 i40 has exactly the same fault. Is there an outcome as it seems like a common fault

 

[luckybricklayer]

In my case looks like the battery replacement solved the issue. For my car (diesel, blue drive with start/stop system) can't be a common one. It has to be AGM type of the battery for cars with a lot of electronic equipment. I can't tell it for sure, but since I replaced the battery the fuse didn't blow yet, so looks promising.
So guys please review your batteries and ensure if they are proper type for your cars

 

[telboy007]

In my case looks like the battery replacement solved the issue. For my car (diesel, blue drive with start/stop system) can't be a common one. It has to be AGM type of the battery for cars with a lot of electronic equipment. I can't tell it for sure, but since I replaced the battery the fuse didn't blow yet, so looks promising.
So guys please review your batteries and ensure if they are proper type for your cars

 

[telboy007]

Hi Guys just to let you know replaced the battery and guess what all working. The media fuse 15amp protects the media unit and also the dc-dc converter (media)
which is a seperate unit which sits behind the head unit and below the scuttle. to access you need to remove head unit. However I am given to believe the converter is supposed to "stabilise"
the voltage to the head unit during idle starting and ISG auto starting. The battery should be an AGM type and when it ages it reduces the voltage but to enable starting the vehicle it ramps up the amps to compensate.
This causes an overload to occur during the starting process, and then blows the fuse accordingly.
The first sign of a worn or incorrect battery is ISG becomes inoperative for a fair while.
Hope this helps anybody in the future.
Good luck guys.