First off let me say this is my first post after just joining the site today. I have been reading info on here for weeks and have used it before as I now own two Mercedes Benz vehicles. So if this is in the wrong spot or if I posted it wrong I am sorry in advanced.

So to the question/problem at hand. I am having tire pressure monitor system issues I know this and I am thinking it needs a new control unit I will know for sure on Friday as I am bring the car into the dealer I got it from and they are going to take a look at the warning lights. I have only had the car for a week now so this is a little disconcerting. That being said the engine light came on the other day when the tire light was on as well and has been on ever sense. I have checked all the fluids and keep checking everything and all is well. I am pretty mechanically savvy so the engine is doing nothing suspect. I am wondering if the engine light might be on because of the tire pressure system? I don't think it would come on for that but I am hoping so. The car has 44,000 miles on it and I have the records for it so it looks like it has been very well takin care of. I was just wondering if any of you guys might have some other ideas as to why the light might be on. Like I said I haven't had the car more than a week yet and the light is on so thats a little worrying. We knew about the tire pressure system when I bought the car so they are looking at that/fixing that for free but I am hoping the engine thing is nothing big.

Separate question I have read a lot about the Headbolt issue and seeing as that to me is a catastrophic issue I was going to see if there are any warning signs I should be on the look for? Or any other things I should keep my eye out for on this beast.

Thank you much!

Found out the error code it is
P0410
Secondary Air Injection System

 

A million reasons why the light is on. No one can tell you why here without the code. Have autozone check it if you don't have a reader.

 

Agree that there's a million reasons why the Check Engine Light is on, but it's worth noting that low tire pressure is NOT something that will ever cause the CEL to light up.

Dealer should be able to quickly diagnose the CEL when you go in on Friday, but stopping at an Autozone or somewhere else that has a reader is still a good idea. . . it may tell you that you don't want to be driving it between now and Friday. Post results here if its not clear and you should get some good feedback.

Dealer should also be able to quickly diagnose your tire pressure issue. It's more likely to be one of the sensors in the tire than the main control unit.

 

Ok I probably will take it by an AutoZone and have them run it real quick because I have been driving it. Do they run them for free?? I was hoping it is just one tire sensor that is messing up but since all the pressures are fine and staying the same and just the way its acting is leading me to believe it is the main control unit unfortunately. Also its not a Mercedes dealer that I am taking it to so that shouldn't matter really should it? The Mercedes dealer close to me I really don't like going to they are a bunch of arrogant *******s. The way I have been treated there is appalling at times which is unfortunate because I own two Mercedes. They are more of the if you didn't buy it from us we don't give a s*** about you not the, oh you own two Mercedes we should treat you not only as a nice person but a loyal Mercedes client. So that makes me only go there if I have to. Thank you all for the feedback.

 

So I went by AutoZone and found out the light is on for the Secondary Air Injection System. So as I figured it has nothing to do with the tire pressure system, but it also sounds like its not that big of a deal which is a nice relief to know it is nothing serious. Sounds like that has something to do with when the car starts pushing fresh air though the exhaust. Sound like an emissions thing to me. If anyone has any info about that it would be much appreciated.It could be one of three things
1)Circuit relay defective or fuse
2)Check connector and wiring
3)Air pump defective or hoses blocked
the error code is P0410
Happy its nothing too serious though!! Any info would be great. The car is so awesome. I am still shocked I own it. She is a dream car of mine that is my second favorite engine ever made, even before I owned the car I've always loved them. The sound is the best EVER!!!! hah I LOVE HER!!
I am happy to be on a message board filled with other MB/AMG fans its great!
Thanks.