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So-not-a good thing

Hi. This is my first post. All of this happened a week ago:

electronic door locks
electronic window controls
parking lights
tail lights
intermittent wipers
door-activated dome light
rear window defrost all stopped working at once.

On the flip side, nearly everything else not listed works perfectly (headlights, radio, A/C, brake lights etc…). To me this sounds like a fuse except I don’t know which one to replace. I couldn’t figure out by my owners manual. Does any one know?



Yes it sounds like a fuse, but there is no way to answer your question with out knowing what car you own.

This doesn’t seem like a fuse to me, because I don’t think one fuse would carry all these items. The rear window defroster alone takes quite a bit of current and should be on its own circuit. There may be a fusible link that carries all these items that feeds the fuse panel that has blown. There may be a feed to the fuse panel that has become disconnected.

Your owners manual should tell you what fuses protect which circuits, unless this info is given right at the fuses.

Agree with Triedaq…it’s not a fuse…

Well, it could be a fuse link… or it could be that most of these stopped working because a fuse that protects a lot of control circuits for these burned out. If the controls/switches for the windows, locks, interior lights, defogger, etc. are all ‘soft’ controls that provide inputs to the BCM and don’t really handle any power. The tail lights and parking lights wouldn’t be on this circuit, but there’s no reason multiple fuses couldn’t be blown, especially if there is damaged wiring somewhere…

So I would still check all the fuses first. I think Roni should take it to a mechanic though, since she? doesn’t understand the owner’s manual.

It is customary to have several large fuses or fuse links that each protect a bunch of smaller circuits, each of them with their own fuse. Usually these circuits are grouped by those going through the ignitions switch accessory position, those going through the ignition switch run position and those not going through the ignition switch.

Your list of things working and not working do not seem to all fall into just one of these categories, so this makes it a little tougher. It seems unlikely that all of the individual fuses would blow at the same time though. It also doesn’t appear that they would all share the same ground point.

Just a guess, but I suspect the problem will be found in the underhood fuse and relay panel, but it looks like you will need the help of an automotive electrician or a good mechanic with experience in electrical problems.

BTW, the owners manual won’t be much good for this type of problem, you need access to a shop manual or AllData.

My vote is with the others for a blown fusible link. With a test light or VOM they’re easy enough to check and if a link has popped then consideraton needs to be given as to why it popped.

What year is your Sonata and how many miles are on it? Older cars are more likely to have a fuse or fusible link problem.

It’s a 2008 Hyundai Sonata 4 Cylinder. I have about 130K miles on it. I did take it to a mechanic and he said it was a Body Control Module. He says that condensation from the air conditioner caused liquid to get into the BCM and that was what caused so many different systems to fail at once.

I’m thinking of taking it to a Hyundai Dealer for confirmation though. I’m down with a part wearing out…it would seem as though the condensation would have caused this much sooner.

Any thoughts?

Is the warranty still in effect?
At any rate Hyundai should give you some rhythm on this.

To check fuses, I like a beeping ohmmeter. Make sure the car is off or else you’ll blow the fuse in your meter. Most stab fuses have two metal tips on either side of the rating number that you can test for continuity without pulling the fuse (0 resistance is a circuit, infinite resistance is an open circuit or unrelated wires. You don’t need a beeping ohmmeter at all, but it’s nicer when your contorted under your dash…

Most of the things not working do not go through the BCM. Try another mechanic.

Yes, it could be the BCM. Not uncommon in newer cars to have this component fail. Older cars don’t have a BCM, they only have fuses. Easier to fix. Page 6-22 is where the owner’s manual explains about the fuses for your car by the way. Ask someone to help you verify all the fuses are working first. If so, you’ll have to get some help from an expert on fixing and replacing your car’s BCM.