CEL and ESC

This morning I started the car with the remote and went out and put the key
in a procedure I've done hundreds of times.

This time, however, the Check Engine Light and the Elelectronic Stability
Control light remained on.

The car drove, but very slow, I think it is a safe mode of some sort.
Maximum RPM was about 1200. I drove around the block, came home and parked
on the street and shut the car off. I restarted the car and it is now
back to normal except the CEL is still on. Drives fine and the ESC light is
off.

Here's what I think may have happened. Last night I drove home in a slushy
wet and slippery snow. The ESC was never engaged, but the ABS did a couple
of times. I parked the car and, of course, the temperature remained below
freezing. Something may have frozen or otherwise affected the wheel sensors
for the ABS and ESC. The short drive was enough to free it up.

My question though, would that put the CEL on? I'm also assuming it has to
be reset with an instrument by a repair shop or possibly the auto part
store.

Any other ideas?.

 

Only time I had the CEL come on was with a loose gas cap. I removed
power from the battery for a minute or two. Light went away.

 

I may give that a try after checking the manual for what I may lose in
memory, if anything.

 

Follow up:

Same problems this morning. Evidently there is more than just a slush
factor going on so I'll take it in the shop this week.

One thing I did notice, the brake pedal seemed low when I put my foot on it
to put it into gear. After driving, it was back to normal and the ESC light
went off.

 

If this is a 2006 or newer Sonata (which it is if my memory is
correct), I'd guess a faulty throttle position sensor or accelerator
position sensor.

 

If this is a 2006 or newer Sonata (which it is if my memory is
correct), I'd guess a faulty throttle position sensor or accelerator
position sensor.

*******************************************************

You guessed right. Dealer fixed it promptly. They also took care of the
recall while there and even washed the car before returning it. Hyundai,
and the dealer, seem to really want to make customers happy.