I have a 2005 XG350L it will be a year old next month and has 6300 miles. I
dont drive much at night but had to last night and noticed that with the
headlights on and the air conditoner running ( climate control ) that
everytime the air kicked on the lights would dim....is this normal, I dont
remember my wifes Santa Fe or our Tucson ever doing it, I could be wrong and
just happened to notice this one. Second concern is when breaking I get a
slight pulsation in the break pedal between 20 and 30 MPH noting above that
or nothing below that. I can see the rotors though the wheels ( custom
wheels ) and they look perfect no ridges ,scatches ECT. front or rear. Any
Actually, I need to ride my bicycle more often... :-)
If I wasn't 20 miles from work, I'd ride to work now and then, but 20
miles, when 5 of that is hilly back roads, takes too long. Lance
Armstrong I'm not.
The lights briefly dimming when the a/c compressor turns on is normal. The
compressor clutch draws a large amount of current when it engages, causing
a brief voltage reduction.
For the brake vibration, your rotors may need to be resurfaced. If you
let the vehicle sit for days without driving, you may be building up rust
on the rotors (possibly on the inside surface you cannot see).
Thanks both John and Hyundaitech
I guess the rotors may need to be checked further, I only drive about once
or maybe twice a week and mostly less than 20 miles round trip, I never
thought to check the rear of the rotors. I did do a kinda no-no ( well
kinda ) 65MPH and stomped on the brakes, the pulsation did seem to lighted
up even more but will have dealer check them out when I get it serviced.
Why is that a "no no?" That may be exactly what you need to cure the
pulsating brakes. Try 4-5 hard stops from 50 MPH or so. If the problem
is rust spots or uneven accumulation of brake pad material, this will
often fix the problem.
HAHAHAHA Matt that is a GREAT IDEA only problem is I take it you havnt ever
been to Las Vegas or havnt been here recently....95% of the time its hard to
get up to 50 MPH. It used to take me about 20 minutes to drive from one end
of the Strip to the other now sometimes you you sit at a stop light for MORE
than 20 minutes and if I were to try that over once on a main highway I
would cause one of the biggest multi-car accidents you would ever see.
Sometimes on I-15 you can walk faster than the traffic moves, other times
its bumper to bumper at 80 MPH. Traffic is so bad here that if you cant get
in the right lane when you wanna get off the I-15 or I-95 you may end up
going 2 or 3 exits past where you wanna get off. I always thought New York
drivers were the worst in the world when I lived there...Now I see most of
them must have come from Las Vegas !!!!! We have the Greatest selection of
braindead, nomind retarded drivers in the world, now you can see why I dont
drive much... I'm afraid it might be catching and I don't want it. Been
driving for over 40 years without as much as a parking ticket and I'd like
to keep it that way.
There are lots of roads not far from Vegas that would be suitable. I
was in Vegas just shy of a year ago on vacation. Flew into Vegas, got a
rental Town & Country and drove around the southwest for two weeks,
spending the last 3 days in Vegas. I actually didn't think the traffic
was bad at all. We drove the strip a couple of times, at both night, to
see the lights, and day to see what we missed at night. The strip was
busy, but that was to be expectd. The side streets and other roads
weren't bad at all. We stayed at a place just a little out of town on
the east side. I believe Sienna Suites was the name.
The traffic there is nothing like Boston, Atlanta, LA, etc.
My 01 Santa Fe did this from the factory, and after mentioning it the
dealer replaced the battery with a 1000 CCA Interstate-branded spiral
cell battery and the problem went away about 95% (theres still a small
dim, but nowhere near as bad). Our 03 doesn't do it with what appears
to be the same "cheap" OE battery that my 01 came with. My guess is
Hyundai's battery OEM doesn't have the best quality control around -
they do seem to start the car and last well enough though...
I'd start with removing the wheels, checking for debris on the mating
surfaces, and properly re-torquing the lugs to their rated specs. If
its been more than a couple thousand miles since you got the
wheels/tires I'd just get it handled as a standard tire rotation - just
mention the pulsation and tell them Hyundais are sensitive to lugnut
Thanks for the suggestion, but been there done that ( torguing the wheels )
but after a couple 60 MPH brake checks the pulsation went away so I think
hyundaitech was right, it may been a little rusty on the inside of the
Still gonna have dealer check them out cause it seems to me that the
calipers should be hitting the rotors at the same time with the same
pressure..... apparently they are not cause the outside the rotor was clean
and shiny but the inside was not. What ever it was the pulsation is gone and
----- Original Message -----
Sent: Saturday, June 03, 2006 2:41 PM
Subject: Re: Couple of small conerns
It depends on the caliper design. Most calipers only have a moving
piston on one side. The pad on the other side is pressed against the
disk through movement of the entire caliper in this sliding mount, not
by pressure directly from the pistion. Thus the force on that caliper
isn't the same as the force on the caliber that is directly actuated by
the piston. The force is the force from the piston LESS the friction
force in the sliding mount, which can be substantial when it gets a
little rusty and full of brake dust and other grit.
So, it isn't unusual at all for the pads on piston side of the disk to
wear faster, and keep the disk shinier, than the pads on the other side.
Well if everything is working right (properly lubricated) the difference
in pressure should be a couple ounces at the most... the more severe
the corrosion/dirt/wear/lack of lubrication the more the pressure
Using the wrong lubricant will gum the slides up badly, be sure to get
the right stuff.
Yes, but the proper lubrication seldom lasts from one pad replacement to
the next, at least not in our PA winters. The road salt, water, dirt,
etc., will remove the lube in one winter. The difference in force then
is a lot more then a few ounces. Keep in mind that the caliper is being
forced against the mount with a LOT of force when under hard braking. A
rusty or even dirty slide will have a lot of friction and will take a
lot of force to move when under the force of heavy braking.
Or worse yet, melt at high temps and get on the pads or disks.
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