Thread: Hyundai electrickery troubleshooting

My partner has a 2012 Hyundai i30 a 1.6L diesel, affectionately named 'the dirty 30' (She never washes it). It's a great little car, super efficient and comfortable enough for the runabout it is... but has just developed a problem.

Today I noticed the first issue we've had with it- both low beam headlights are dead.

So this evening I donned a headlamp torch and the multimeter, and did some testing- which proved inconclusive. I'm unsure if this is one of those vehicles with something tricky going on in a circuit(s) that should be pretty simple. Any advice welcome!

Testing shows:
1) 12.34 V at the battery
2) Headlight fuse (both LH and RH Low beam - presumably 2 circuits) are intact.
3) Continuity between battery + and fuse
4) Continuity between fuse and headlight connector
5) Headlight relay clicks when headlight stalk switch is switched from park > Lo beam (not a sticky relay)
6) No voltage present at the headlight connector with the low beams ON (I triple checked- both LH and RH light connectors).
7) I didn't check continuity of the globes due to the lack of working space, but assumption (the mother of all F-ups) makes me think that they are OK.
I should note that both headlights have failed at the same time, leading me to suggest globes are OK.

Given that there is 2 fuses (1 for LHS, 1 for RHS), and presumably 2 circuits I'm guessing this rules out them being wired in series? If wired in series, if 1 globe blows, the other will not work.

Is there any other tests I should do before I approach the dealer to have a Look (vehicle is still in warranty, if it's in fact an electrical fault, not a globe fault)?

Is it possible that Lucas, the lord of darkness has left my Puma, and infiltrated the innocent i30?

It sounds to me like poor quality globes. I found a long time ago Phillips was the only brand that would lest in taxis and I don't expect it has changed much over the last few years. If the globes are going black it is a hint that there is an earth problem. If the elements are coming loose it is very poor quality solder.
Good luck with the replacement globes.

Originally Posted by Toxic_Avenger

For those playing around at home, had it checked out by the dealer.
Apparently the BECM switches the headlights, but still confused as to why both globes went at the same time. Some websites / hyundai forums suggesting that voltage spikes in this vehicle have a history of destroying globes. Some owners have experienced 20+ blown globes over just a few years of ownership.

It's got a service record against it now, so we'll play it by ear.