Yesterday I changed my HID headlight ballast on the drivers headlight. Removed the grill, bumper cover, etc. to complete the project. The headlight again works, but now my car won't start. No crank, no turnover. It won't go into neutral or anything; that part is locked. I tried to jump it, but nothing. The headlights turn on and when I put the key in the ignition, the dash display says "Remove Key From Ignition".

I can't imagine what I may have done to cause this. I can't recall any parts that were shoved or anything like that which had anything to do with making the car run, but I'm also admiringly not very knowledgable.

Wondering if any of you may have suggestions on what it may be. In the meantime, I'm going to get a multimeter so I can check the fuses for the Starter Circuit, Ignition, EIS, and Fuel Pump, to see if any of those possibly blew somehow.

Thanks guys

So I used a multimeter to check the fuses for the Starter, Ignition Lock, Steering Lock, Fuel Pump, Central Locking and Engine Electronics. All fuses were good. Was really hoping it was just a fuse.

You might have triggered the front collision sensor when removing the bumper, causing fuel cutoff to engine safety precaution to kick in.

So I realized that the brake lights are not lighting when the pedal is pushed. That fact along with the car being unable to get out of park, are leading me to believe that somehow the Brake Light Switch has gone bad. I'm really confused though since the headlight job was nowhere near the Brake Light Switch. I have a bad feeling that I'm going to replace it and still have the problem. Either way, I'll go to the dealership and buy one ($36+) and see if it does the trick.

Any other ideas are welcome.

Oh! I hadn't considered that. That makes more sense then the brake light switch. If that sensor were triggered, would it cause the brake lights not to light up when pushed?

And if this were the case, what's the resolution?

I would say your ESL is failed.
Do you hear steering lock trying to disengage?

I had this happen to me when doing interior work and removed the seats. Took a STAR system reset.

Well, it wasn't the brake light switch, which I assumed it wasn't going to be but figured I'd try since some of the symptoms were matching and it's a fast, cheap fix.

Due to running out of time to fix it myself before morning, I had to get it towed to the dealership. $300 for the tow. They were out of all of their loaners so I had to get someone to take me to Enterprise to rent a car until a loaner comes in. They said they won't get to it for a few days. Sucks. I'm a stay-home father so I try to do everything I can myself to save money at this point. Taking a big fat loss on this one though. Super bummed about that.

Thanks for the input, guys, I do appreciate it.

So what did the "stealership" say? I'm having the exact same issue and don't have thousands of dollars to repair

It sounds like the electronic steering lock failed. Easy to check if you have a scanner capable of checking codes in the electronic ignition switch. Usually you will get a codes that say something about mechanical failure of the ESL.

Did you ever find the solution? Having the exact same problem. Changed the ballast now car wont start. But started before ballast was changed

shot in the dark here, it could be your steering wheel lock mechanism. When that fails your car won’t start. I had this happen in my x204 and it failed due to an electrical issue. Unfortunately it has to be replaced by the dealer, they charged me about $1200 for parts and labor.

[QUOTE=almac04;8958050]shot in the dark here, it could be your steering wheel lock mechanism. When that fails your car won’t start. I had this happen in my x204 and it failed due to an electrical issue. Unfortunately it has to be replaced by the dealer, they charged me about $1200 for parts and

Did you ever find the solution? Having the exact same problem. Changed the ballast now car wont start. But started before ballast was changed

Are we talking original Mercedes HIDs, or is it an aftermarket HID kit?

I am referring to the ballast. Not the HID light itself. I started the car before replacing the ballast to turn the wheel. Got under the car, took the old ballast out, put the new one in and the car wont start at all. Checked all fuses. Car wont show dash lights when the key is in the on position. Brake lights dont show at all while pressed! Im thinking i either blew something or threw the computer off. Cause i literally cant boil down to what else it could be

The OP appears to have an 08 W204. i dont have OEM HID headlights so i looked up what they look like on eBay. Is this what your headlights look like?

yes that's what it looks like. But it has to do with that ballast I changed out. Because everything was perfect before hand

Ok, so you replaced the control unit Part#20 in the diagram?

yes looks different but yes. The headlight ballast

Is the battery fully charged? Check battery terminals with a multimeter.