Warranty just ended, cruising 80 on highway and service engine light comes on. No loss of power, no weird sounds, nothing. Bone stock. Turn engine off, restart and light is still lit.

Any ideas? Worried it is something serious...but probably just faulty sensor, right?

 

Not to be a *****. But people that post like this drive me crazy. Did you pull the code? If you didnt how can anyone possibly help you. DUH

 

Take it to your local autozone or pepboys and have them pull the code for it, then come back here and tell us which it is. No sense in guessing what it could be as there are tons of possibilities.

 

how are you out of warranty @ 36xxx?

warranty was 5 yrs or 60k on my '03 at least....

 

...

reset your ecu, and see if the light is still on. You can reset your ecu by unhooking the battery, or unplugging the outside connections to the ecu harness.

If it is still there/ or if you would like to know what the code is, go to autozone and ask them nicely to use their obd2

 

Cruising at 80mph and it just clicked on...sounds like the dreaded P0300 code -- random misfire. Same happened to me. However, everyone is right. Make sure and get the code pulled, then get back to us.

Wouldn't worry to much if the car still runs fine.

 

Thats the powertrain warranty. The bumper to bumper warranty is only 3yr/36k.

 

engine/drivetrain to be specific ( unless im wrong)
wouldnt this fall under that?

 

My 8-ball says your CEL is for not getting enough fiber in your diet. Am I close? :P

 

Yeah definitely reeks of P0300. Dealership can flash, fixed mine and it never came back.

 

I thought 03s were 3 year/36k mile and 04s were 5/60k.....

Also, don't worry. SESs are normal with DSMs (unfortunetly) Pull the code and go from there as everyone says.

 

Everyone has to start somewhere I suppose...

 

Yes disconnectin the battery may turn off the light, however the ecu stores the last codes thrown. The only way to truely get rid of it is get a microscan/codereader and physically delete the code from the computer. Just thought i'd give some insight to this, as alot of people are under the impression disconnecting the negative deletes the code.

 

I am pretty sure the power train warranty only covers mechanical parts and not sensors or things like flashing the ecu (for the po300 code). I could be mistaken because I work at Mercedes where the warranty is straight 4yrs/50k bumper to bumper. No separating powertrain and regular warranty.

 

if you didnt feel anything jerk or act weird i wouldnt worry, go get the code read and erased. that should solve your problem