Dim Headlights on a 02 Santa Fe

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Ok..Let me know if anyone has a clue on this one.  My daughter has been
complaining about her headlights not being quite bright enough, so I marched
out with my trusty voltmeter and checked it out.  The negative (pink with
white line) wire to the bulbs is sitting at 1.5 volts above 12v negative
battery ground.  I'm showing that with the engine running and 14.1 charging
volts, the headlamps are getting an effective 12.5 volts.

Any ideas here?  Has anyone seen this before?  Any help would be much

Regards, Jim L.

Re: Dim Headlights on a 02 Santa Fe

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Update:  In order to find out where my 1.5 volts was going, I pulled the
headlight relay and substituted a jumper to ground to eliminate the relay
and relay ground from the picture and was still missing my 1.5 volts to the
headlamps in the way of an inadequate ground.

In my way of thinking, this only leaves a bad headlight switch. One with
some internal resistance.

My neighbor has a 2001 Santa Fe, so I prevailed on him to let me measure the
voltage on his headlamp ground and it was about   .7 volts.  Not monumental,
but some less.

So now the quandry...do I take it to Hyundai and let them tell me it is
within acceptable limits and my daughter needs to take off her sunglasses at

When I directly ground the headlamps, the brightness comes up measureably,
so I could give her a switch on a ground jumper....sort of a semi
hi-beam..(:} just joking...  I could get some hi intensity headlamps and
call it good...just thought of that one but it is sounding better just as I
type.  Anyway, Thanks for the sounding board!

Jim L.

Re: Dim Headlights on a 02 Santa Fe

I'm showing in the schematic that Red is power, White is low beam ground,
and Gray is high beam ground.  So first, I'm suspicious that you're
testing the wrong wire (but I've also seen the schematics incorrect, so
you could very well be on the right track, too).  

Second, before you start hunting the voltage drop, check to see whether
the bulbs are installed correctly and the lamps are aimed well.  The
number one cause I've seen of complaints of dim or improperly aimed
headlamps is improper bulb installation.

As for your voltage drop, I'd suspect it's largely in the junction block.
If you've tested everything correctly and you do indeed have a 1.5V drop on
the ground circuit, I'd say that's too much.  I also think anyone who says
that anything more than 1V drop on this type circuit either doesn't know
very much about automotive electricity or doesn't actually want to do the

Re: Dim Headlights on a 02 Santa Fe

Thankyou Hyundaitech!  I haven't checked bulb installation....I need to do
that and then actually take the vehicle out after dark to see how the aiming
is.  I appreciate you getting me back to the basics as I tend to get off on

As far as the Ground wire, on this 02, the ground is definitely red
(actually Pink) with a white stripe.  I grounded it to the chassis with a
jumper and the headlamp brightness came up measureably.   This car is a
special case because it was a salvaged car and even though it has under 60K
miles, I'm afraid I may get some frowns at the dealership.  I may still try
that. All the electrical and mechanical was intact through the rollover, but
the roof took a bit of a beating.

Rather than replacing the junction block, I may mount a relay under the hood
and supply a local ground through the relay when the lights are turned on.
I talked myself out of brighter headlamps because they would just draw more
current and my 1.5 volts would probably go up over 2 volts.  I would get
nowhere besides the fact that I would be overtaxing an already questionable

I think I will give Hyundai a call and see what they say.

Thanks again for your help!  You are a Godsend!

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Re: Dim Headlights on a 02 Santa Fe

If you want to post your vin, I'll check it to see if your car is listed as
salvaged by Hyundai.  If so, there won't be any warranty.

Re: Dim Headlights on a 02 Santa Fe

Very Cool...Thankyou!...The VIN is KMFSC13D02U226888

Best Regards,
Jim L.

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Re: Dim Headlights on a 02 Santa Fe

Ran VIN KM8SC13D02U22688.  Notice I changed the F to an 8.  That should be

Message from Hyundai:
Mileage altered-- not warrantable.

Re: Dim Headlights on a 02 Santa Fe

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Note when buying used cars... Carfax is your friend.



Re: Dim Headlights on a 02 Santa Fe

Thank you Hyundaitech!  Your right about the VIN...sorry about that.

Surprizes me about the Status.  Maybe the warrantee was writen off for
mileage because Hyundai lacked other options ..I'm sure the mileage is ok as
the breaks and tires are original at 50K and I have some info from the
previous owner.  It had 30K on it when I acquired it two years ago.  I
bought this vehicle from an insurance yard for very little.  These yards are
protected from things like speedos being changed between delivery and
auctions. It was rolled in the soft snow on one of our wintery days. I
pulled out the headliner and pushed the top back out (can't tell now except
from above.  I replaced the windshield (the windshield frame was fine) It
didn't even hurt the rack. Some wrinkles in the doors, but everything fits
and opens and closes like new. The Santa Fe didn't even need an alignment.
All the fluids were great.  The original battery lasted until this winter.
This great car has been virtually trouble free for two years and I don't
consider this headlight thing a big issue.  I will take care of it this
weekend. (I'm a technician with a lot of automotive electronics experience).
I will put in a relay to take the low beams to ground locally (to the lamps)
I really want to max the current to the lamps and even .7 volts loss is more
than I want to deal with.  100 ma. through the coil of a relay rather than
the 5 to 6 amps of  lamp current should make that original switched ground
path last the life of the car.

Really, this car owes me nothing and not having a warrantee is not an
issue...it would have been a bonus, but I don't really believe I deserve it.

My daughter loves this car and when we first got it for her, she wanted me
to get the doors fixed and get it painted.  Now, she has decided she likes
it just the way it is.  She can park it in downtown Seattle and not worry
about door dings.  When she gets on the freeway, people give her plenty of
room.  Inside it is luxurious, quiet, and is really reliable.

I am sold on these cars!
Thanks again Hyundai Tech!

Jim L.

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Re: Dim Headlights on a 02 Santa Fe

Maybe they just classified it incorrectly and meant to classify it as
salvage.  Dunno.

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