Hyundai Check Engine Light On

Hyundai has become one of the most reliable car manufacturers out there. The fact of the matter is however that even Hyundai cars can turn on the Check Engine Light (CEL) if there is an engine or emissions related problem.

Hyundai check engine light can be triggered for several reasons which we discuss in this guide. 

What does Hyundai Check Engine Light Mean? 

In a Hyundai, the check engine light comes on as soon as the onboard diagnostic system (OBD) detects that there’s an issue with the way the engine operates or Evaporative Emission Control System (EVAP) which is used to prevent gasoline vapors from escaping into the atmosphere.

A fault code stored in the Engine Control Unit (ECU), explains what caused the check engine light to come on.

If the ECU has detected a fault code and triggered the Check Engine Light (CEL) / Service Engine Light, don't necessarily assume that there is an engine problem. The problem could be an emission related problem and the car may drive fine. Still, don't ignore the CEL light.

The first step in the diagnostics process is to read the fault codes via the OBD2 port under the dashboard. You can read the codes yourself or have an auto mechanic. An auto mechanic or dealer technicians use specialized equipment (OBD2 scanners) to read the code from the car’s computer (ECU) via the OBD port. 

check engine light on hyundai santa fe

How to diagnose Hyundai check engine light

Reading Hyundai engine fault codes is easy. A Hyundai owner can read Hyundai engine fault codes using and OBD2 scanner connected to the OBD-II port under the dashboard (see instructions below).



  1. Locate the OBD-II port. This is a 16-pin port located under the dashboard on the driver's side.  hyundai sonata check engine light on
  2. Plug your OBD2 scanner into the OBD-II 16-pin port.  hyundai codes for check engine light on
  3. Turn the key to on. All the dash lights should turn on. Don't start the engine.  

    turn hyundai igntion on to diagnose check engien light on
  4. Scanner turns on. Hit SCAN or READ button on your OBD-II scanner. You will see fault codes such as P0300. Write down the code and do research online on what those codes mean on Hyundai cars. 

    hyundai check engine light on clear codes
  5. Read fault codes. 

Fix the problem that caused the check engine light. You can use the scanner to clear the code or drive the car for a couple of days and the light will turn off after four or five driving cycles.

Common Problems

EVAP Codes

Typically when Hyundai check engine is on but car drives fine you most likely have an Evaporative Emission Control System (EVAP) code. EVAP is used to prevent gasoline vapors from escaping into the atmosphere from the fuel tank and fuel system. 

how to clear hyundai check engineIn many cases that the check engine light turns ON in a Hyundai (Elantra, Sonata, Santa Fe, Accent) the car may still drive perfectly fine. This happens when you have a emissions related problem. 

The problem here may be something as simple as a loose gas cap. Retightening or replacing the gas cap often will fix the check engine light. If the problem is a loose or defective gas cap and you address that problem, the check engine light will turn off on its own usually in a couple of days. 

Related fault codes:

  • P0440 Evaporative Emission Control System Malfunction.
  • P0444 Evaporative Emission Control System Purge Control Valve Circuit Open

  • P0422 Main Catalyst Efficiency Below Threshold (Bank 1)

  • P0420 Catalyst System Efficiency Below Threshold (Bank 1)

Hyundai check engine light flashing/blinking

If your Hyundai check engine light is flashing and the car is shaking, that means that you have a serious engine malfunction and you should avoid driving your car. Check engine light flashing and blinking is a result of an engine misfire.

Replacing the spark plugs and spark plug wires is all that you need to do to fix this problem. In some cases, the check engine light may flash due to a bad ignition coil as well. All these are easy and inexpensive repairs and can be performed by any DIYer.

Don't continue to drive a Hyundai that has triggered the check engine light and is shaking; you may cause serious damage to the engine. Not only that but if you are driving in heavy traffic, your engine will overheat. 

Related fault codes:

  • P0300 Random/Multiple Cylinder Misfire Detected

  • P0301 Cylinder 1 Misfire Detected

  • P0302 Cylinder 2 Misfire Detected

  • P0303 Cylinder 3 Misfire Detected

  • P0304 Cylinder 4 Misfire Detected

Check Engine Light on / No Acceleration

what does check engine light mean on hyundai sonataIf your Hyundai will not accelerate and the check engine light is on, it is very likely that a faulty throttle position sensor.

Under these conditions, the car will barely move or not accelerate at all. Replacing the throttle position sensor is easy and can be completed by any DIYer in less than one hour.  

Fault codes related to Hyundai CEL on, the car won't accelerate. 

  • P2135 Throttle/pedal position sensor/switch A/B voltage correlation

  • P2135 OBD-II Trouble Code: Throttle/Pedal Position Sensor/Switch ¬†A/B

  • P2106 FORD Throttle Actuator Control System - Forced Limited Power

  • P2127 Throttle/Pedal Position Sensor/Switch 'E' Circuit Low

  • P2138 Throttle/Pedal Position Sensor/Switch 'D'/'E' Voltage

  • P2101 P0222 P0123

Hyundai Check engine light and ESC on

If you both the check engine light and the ESC light come on this means that the accelerator pedal position switch has failed. In such cases, the car will lose all power.

Pressing the gas pedal to the floor will not change engine RPMs. The car won't accelerate but you can get your car up to 20 MPH. Try restarting the car as this may fix this problem temporarily. Hyundai sells a redesigned accelerator pedal position switch that should fix this problem.

Replacing the sensor at the dealer or a repair shop costs between $200-$450 USD. Installing a used Hyundai Accelerator Pedal is another possible solution. 



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user profile image
Visitor made a comment.
1 year 1 month ago

Engine light is on. Drives fine. But when I Idil there is a rumble to the car.

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Hyundai santa fe made a comment.
1 year 1 month ago

CEL on and car cannot speed up..why?

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Visitor made a comment.
1 year 1 month ago

You need to read the codes as there are thousands of codes that could have triggered the light to come on.

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John111 made a comment.
4 months 1 week ago

How to clear a permanent code p0011 please?

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Ruel duatin made a comment.
4 months 1 week ago

Why my check engine never goes on even the ignition switch is in on position

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Bert Censon made a comment.
2 months ago

My hyundai santa fe, check engine light on while I'm on the high way

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ALAN FAIRCLOUGH made a comment.
1 month 1 week ago

2008 Santa Fe with steady check engine light on. Code reader says oxygen sensor bank 1 . I have replaced both oxygen sensors and the old ones were tested good. Replaced spark plugs, fuel cap, intake manifold gaskets and much more, over $1000 spend with no joy. I cannot get it inspected now. They require I drive 50 miles after resetting. It comes back on after 30 miles. The car has 80.000 miles and runs perfectly.
I understand Hyundai dealers have not been able to fix it either.

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Malek made a comment.
1 month ago

My Hyundai Getz 2008 just suddenly got the check engine light just like that not flashing or blinking and it drives fine

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Elizabeth G. made a comment.
5 days 8 hours ago

This was very very helpful!! Great, simple explanations for the not-mechanically inclined!!

p.s. What about check engine light and slight vibration at low speed?


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