Indicator lights work after keeping the engine going for a while

What have any mechanics done?
Do you have an aftermarket alarm? If so, does it disable the ignition? I have seen many, Many, aftermarket alarms go bad and give an intermitent problem.
Has anyone replaced or tested an ignition module? Auto zones can test modules for free.

most auto parts stores can check your alternator and battery while it is in car. look for national chain auto parts store and they will be happy to help you most for free

The two lights you mention are also two separate systems in the vehicle. There is always a code set when the Check Engine light comes on. Find an OBDII scanner & scan the ECU (Engine Control Unit) to find any codes. I need to know which code(s), there may be more than one. The Airbag light is a proprietary (Hyundai specific) system with unique coding. That particular system can only be diagnosed by a qualified Hyundai Technician and the appropriate scan device (Hi-ScanPro). Check with your nearest Hyundai Dealership... I doubt that 1999 Accent is still under warranty.

well the first thing you need to do is to pull the stored codes in the computer and see what they say and then go from there, this could be a speed sensor or a trany going bad , i dont know if this is an automatic or standard trany, start with the codes from the check engine light, autozone car parts store will scan the computer at no charge,

Hi:
There are hundreds of reasons the check engine light comes on, some so simple as a loose gas cap...A good way to find out what is going on is to stop at a local auto parts store, and get them to scan your codes for free. That way you will know what caused the light, and can decide if you need to have it repaired or if it is a minor cause.

hi my name is pete glad to help code p0442is indication an evap emission <small leak > your car is ok to drive but would not pass the smog test i would advise you get a pro to sort this as the code dose not tell you where the leak is i know the canister close is located under the vehicle next to the canistertank good hunting

Usualy the check engine light reports a malfuction in your engine performance system, it coulb be a misfire, bad sensors, vaccum leak, you need to have your engine code read from a garage or an auto parts store that offers the service for free.

ok when the check engine light comes on that usually indicates a engine malfunction...what you can do is go to your local autozone and they can do an OBDII test for free..my bet says it is the cam or crank sensor.. DO NOT SHUT THE CAR OFF AT AUTOZONE..LOL

This is because there is a leak in the muffler and this light indicates increase in oxygen detected by lambda sensor... so nothing serious but you might be injecting little extra fuel causing little decrease in mileage... to fix this just replace or weld the muffler or most probably the flex pipe

HI

I think the cause can be a poor grounding connection in engine
that cause the (Oil,battery,door and hand brake lights all go on)
and no check engine light because of the (ECU) not work good
depending of no power in it because the poor ground ??

send more details after test to have more help

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