Reading MIL codes on 2006 Sonata

No way without a code reader. Take it to advance auto, auto zone , etc. They will read it for free. And don't take it to a stealership for repair, take it to neighborhood mechanic.

Does Hyundai provide a way to "read" check engine light codes without having a code reader? I am thinking the way that you can read many GM cars by shorting two pins in the diagnostic connector, or Chrysler's where you can turn the key on-off-on-off-on quickly and have the code flashed on the dash. Any such feature in a 2006 Sonata?

My check engine light came on today and I'd like to get some idea what it is before taking the car to the dealership.

I heartily recommend buying a code reader! It's one of the best investments I've ever made. Right away, you can interpret the code and know whether the you have to stop driving this second or your engine will explode. Or that it's, in fact, a condition that requires no rush.

The programming of the car's computer is very sophisticated, and the system actually interprets conditions, some over a period of time, before turning on that dash light. A code reader will reveal stored and pending codes that have not yet turned on the light, so you can see potential problems in advance.

The code reader is not as informative as a mechanic's scan tool, which provides some detail behind the codes. This is more expensive.

I tried three different brands. I definitely prefer the type that does

*not* tell you the problem on the screen in English, but gives you a simple numeric code. You look up the meaning of the code.

A reader like this does not become obsolete. The fancier ones often need to be re-programmed when you get a newer vehicle, and you pay for the re-programming.

Mine was sold under the name "Equus" but the actual Taiwanese manufacturer's name is different (I forgot). I feel that it's well-designed.

Richard

Agree with the parts store suggestion for reading the code. But *do not* t ake their advice on repair. I had a car in my bay a few weeks ago with a b lown fuse (due to a wire rubbing through) that the parts store advised them they needed a purge valve and had a vacuum leak.

Once you have the code, you're probably more able to research what it means and the likely causes than they are. If you'd like, you can report the co de here and I'll give you my thoughts.

Whether you should take the car to the dealer for repair depends on the pot ential warrantability of the issue, your comfort level with the dealer and local shops, and the type of issue being diagnosed-- the dealer's proprieta ry tools may have particular testing capabilities for the issue in question .

And Richard makes a good point regarding purchasing the code reader. It's a handy think to have. A basic one (with CAN communication capabilities) w ill check powertrain codes on all 2006 to current models. I figure you sho uld be able to get one for $100 or so.

You can get a code reader cheaply on eBay. The one I'm using cost under

35 bucks and works fine. I don't use it very often by I did use it last week when the check engine light came on. The reader gives the codes and states the problem in English. It said the fault had something to do with a lean mixture in a fuel bank. I can't say what would cause that but I reset the light and will wait for something to fail. It's handy to have one on hand but it's also fun to dick around with it cause it also gives real time readings of your engine and systems.

My wife took the car to a local repair shop and they didn't give her the exact code but described it as an "evap slow leak" and reset it. They said it could be a rusty gas cap. I checked the cap and the filler neck is not rusty and the gasket didn't look to be all that bad, it it sounds like there is some leak that is preventing the system from maintaining a vacuum in the evap system.

Any thoughts as to what might cause this other than a bad gas cap?

I will see how fast the code comes back on.

Without the code any suggestions would just be a WAG. With the code, we can make a SWAG. When it comes back on, go get it read and report back here.

Any thoughts as to what might cause this other than a bad gas cap?

I will see how fast the code comes back on.

Overfilling can cause it too. Was the tank just topped off? Given the age of the car, gas cap gasket would be somewhat expected.

Leading potential causes:

-- improperly installed fuel cap

-- canister close valve (seals system for vacuum and leak-test purposes) does not seal

-- actual vapor leak (most often in canister or auxiliary canister on this vehicle).

A CAUTION ABOUT CODE READERS!

Code readers have a button which will turn off your "Check Engine" light. This doesn't just turn off the light. It clears all stored codes and, as I recall, clears the monitors.

The "monitors" are a group of overall routines that ensure that testing has been completed in each of a small number of function groups. And certain driving sequences have to be completed a few times over periods of time to complete these test cycles.

In normal driving, sooner or later, all of these sequences will be completed to satisfy your car's computer programs: each monitor will be completed. On my code reader, a group of monitors are displayed by their names: when they haven't been completed, they blink.

Completing these sequences can be hastened by driving the car according to precise scripts, called "Drive Cycles." I described my hair-raising experiences in running the drive cycles for my 2000 Sonata much earlier here on this newsgroup.

In California, and maybe other U.S. states, too, your car will flunk the smog test if the monitors have not been completed. You have some leeway in this: the last time that I checked, you were allowed for two monitors to be incomplete.

The monitors just indicate that the car's own testing has been completed. It they do not show that the car won't produce excessive emissions, fail specifications, etc: the car can still fail the smog test.

If you clear the dashboard light, clearing stored codes and zeroing the monitors, then go for your smog test, your car will fail because the monitors won't have been completed yet. You'll have to bring the car back to the test station after enough driving has satisfied the computer. This may take a couple of weeks or maybe longer.

And if you were in a hurry because your registration expired tomorrow, you'll be driving on expired registration in order to complete the monitors.

So, think clearly before shutting off that dash light. In most cases, when you take care of the problem that caused the light to go on in the first place, the light will go off automatically, but may not extinguish right away: a set number of restarts may be required. So, patience, and a lack of urgency, are helpful.

I apologize for the tortured English that I've written, but I've been talking the lingo of the trade: in normal English, one does not "complete a monitor."

HT: Please correct me if I've said something that's not right.

Bottom line: Don't clear the dash light and then go take a smog test in California on the same day! I think that if you clear the light, you should drive for a couple of months, then take the car in for the test.

The vehicle will also fail if the lamp is on, so there's no harm in clearing the lamp (other than deleting the diagnostic information and resetting unrelated monitors).

For most people, driving the car a few days over a mix of city and highway driving will run all the tests.

If the lamp is left to extinguish itself upon repair, the code is still likely to remain in memory, causing an emissions test failure.

For most people, clearing the lamp upon repair and driving a few days is the best solution.

I've had a couple cars which the customer couldn't get all the monitors to run. In these cases, driving them home overnight and back to the dealership the next morning was sufficient.