-2JZ-

Hi,

So i've had this issue come up today and i'm absolutely stumped.

Symptoms:

Today my W210 would not seem to recognize my key fob. The door unlock, lock, and trunk buttons would not work at all when pressed. In addition, when i insert the key into the key slot, the car does not recognize the key. There is no sound such as what i believe should be the pin unlocking the steering column, and i cannot turn the key at all. If i leave the key in and open the door, i get a notification to "Remove Key", however this is the only response i get to the key at all. Otherwise nothing comes up when i put the key in. The car itself has power, radio can be turned on, lights etc. All seems fine there. The whole system was working perfectly yesterday.

Things i have done so far:

1. I took the key apart, pulling out the board and inspecting it. I cleaned the IR receiver with an alcohol q-tip.

2. I also inspected the transponder coil, a very common failure point where the solder breaks off, however mine seems entirely intact. I have included pictures of it.

3. I cleaned the IR window on the key and in the keyhole in the car.

4. I replaced the key's batteries hoping at least the RF transmitter would work and i could unlock and lock the doors. This did not work. The key light blinks red when buttons are pressed, indicating that the battery is fine. Yet no response from the vehicle.

I'm stumped, is this an EIS issue? I really hope not as from what i have read, its very expensive. I also have no way to move the car, i cannot put it into neutral. So what are my options? Any suggestion on what to do or what the problem is? Any fuses i could check? I would appreciate any help. Thank you!

Here are some photos i took:

raymond g-

try looking in a different direction: what is the voltage reading on your car
battery...at rest and under load?

Deplore

Bad EIS.

You can put car in neutral with a pen.

Shove a pen in the bottom portion of where +/- thing is... you don't have to pierce the rubber cover -- just walk it out and then shove it in.

EdzBenz

I'll throw this out there. Did you try your spare key? You could just have a bad key. I ran into this problem with my car a year ago. The key failed to be recognized by the engine computer when I would insert it into the ignition. I tried my spare key and it started up immediately.

MacVidMB-V8

Anyone coming here with bad key issue similar to OP.

Third pic down shows close up of obvious water damage.

Silver rectangle with black circle is the lock button. Chip with silver legs right below it is one affected here. Had someone send me one like that. All I needed to do was use a toothbrush and alcohol, clean corrosion off those pins. When water hits powered pins, electro-migration basically moves metal and salts just like electroplating.

As the black plastic keys age, the buttons crack and water gets in, here you see it right below the switch. I have seen similar damage on several keys. If you get it working, buy a new outer key case and keep keys dry in future.

mrboca

Have you done the Infra-red test with your smart phone or a camera? If there is no IR glow when you press any button on the camera screen, your processor is not running. In this case it could be a bad crystal.

Where are you located ?

WalterParker

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dwillia3476

Did this turn out to be your 7.5 number fuse thats located on the passenger door fuse box?

zengshengliu

DELETED (replied the wrong post)