03rnc32

03 c32 Keyless entry has been acting up for a while. I used to be able to unlock the doors from 500 feet or more. Now I have to hold the remote against the drivers door handle to do anything! This started shortly after the dealer fixed my leaking intercooler gasket a while back. The problem comes and goes. Before it used to happen once in a while, but now it has progressively has gotten worse. Almost completely constant close range now with once in a while can unlock it from a ways away. It does still come and go. I checked two different remotes with fresh batteries. I am thinking a loose connection in the car. Any ideas on what to check or where the system is located in the car?

91RS

Are your windows tinted? You may want to check in the regular W203 forum, I seem to remember seeing a good bit of info on keyless entry problems.

MIKESV8

doesn't the signal come through your handle? it could be the issue. or just pay your stealership to do a diagnostic and figure out the issue.

AMG Sleeper

I was having the same issue recently, and my tech told me either I need a new battery, or I could just order a brand new key, which has better infrared sensors on it, and cool features like "summer" mode when you hold the open button and the windows and sunroof all open for you. The 2012 keys are chrome, have individual buttons, and look pretty cool. But it was a pretty penny... Cost me $228 but I got it within 2 days (I justified it because I didn't have a spare anyway!)

Good luck!

loudandheard

The old keys have that too, even my old 1996 c220 had that feature. The feature would hardly work because the infrared sensors would not pick up the signal because of the sun. You had to be right at the door handle to get it to work.

I've been experiencing the same issue and I'm thinking it has to do with a module, but I gave up on looking for it. Sometime I have great range and other times nothing. I'm going to try replacing the battery in my key to see if it helps.

03rnc32

I asked the dealer to look at it two services ago and they said it was fine and charged me 150.00. It comes and goes. I thought there might be a sensitivity adjustment for the range. does anyone know of that? thanks

GTibunny8v

The antenna for RF locking/unlocking is in the rear windshield. The antenna amp aka a comm bar could be going bad or the double sided tape holding it up could be failing.

Apox

Do you know if you can get this key on a C32 as well?

JonMBZ

yes all keys are pretty much the same except for ones that have no trunk button like a c coupe or G wagon some keyless go keys do not have the latest key design.

03rnc32

I did have the window tint replaced because of bubbling of the tint on the back window which messed up some of the defroster bars on the rear window. Can you explain a bit more on that rf antenna. I think GTiBUNNY8 might be on to something here!

rghatlops

I am having the same issue. I have heard a few mentions of the rf antenna or radio amp in the back window. It seems the antenna is in the rear widow. Does that require a window replacemment?

ggbenz

having same problems!!!!!!!!!!!!! I recently took my c230 to have my tint removed and new tint put back on... when i left there all 3 of my smart key locks were no longer working, but worked perfectly when i got there... come to find out by mercedes benz that pretty much everything that controls the smart key is located in the rear window glass (which was where the tint and removal was done) what they could have done to effect this? I had the company remove the tint in the back window for other reasons such as bubbling, once the tint was removed I then tried the smart keys to make sure that the problem was not coming from the tint itself. They still did not work... The car was locked with the smart key when i got there... in order for them to pull my car in their garage to do the tint they had to unlock my car before it went in their garage... therefore it was WORKING! The problem im thiinking is during the removal and re-tinting process. something obviouslly came loose, and more then likely pressed against. i know this because days later the smart key worked for a period of 5 mins when i put my visor up in the back window..... then stopped working completely as of now. there are also NO malfunctions coming up. which means, the car did not generate this problem it self. according to mechanic... so, few days later my smart keys began to work again...yay! right! NOW all my radio stations are 90% static! all of them!!!!! mercedes advised me to take off back window tint to make it easier for them to see if something was cut/or damaged in the window... but they cant garantee they can find it because it could be very little...they also hooked my car up to the STAR machine and some short something machine and it said it couldnt pick up any channels... they are telling me this def has something to do with them removing my tint... and i might have get a new windshield! sooo much money!please help

Kotat90

I know this about 2 years ago, but Im hoping you or anybody can help me out. Two days ago, I got the clear tints on my 04 C240 removed, and had dark charcoal tints placed on them. All 4 doors, my back window, and also 3 inches of my windshield. I was able to use the keyless entering to drive my vehicle the same day. But on the next day, my smart key stopped working. i changed the battery and everything and it still doesn't work. Unfortunately for me, my manual key doesn't turn when i put it in the key hole, so now I'm pretty much locked out my car. Anything suggestions on what to do or what caused it? I'm thinking about getting a spare key from the dealership and trying to find out why my manual key doesn't work. Help please?

Khan 55

I had the same issue with my car. thought it was a bad remote key. Wife tried working on it and one of the components disappeared. Had no option but to buy a new key which cost me in the region of R2800 which is approximately $220 or so. Included was the new metal slide as the key is a new design like mentioned above chrome housing with separate buttons but that's how my old key buttons were. The key seemed to work better now as I had also disconnected the battery for some reason and reconnected it after a long time. Maybe try and do that and see if things work better from there.


My old key only use to open the car when on top of the handle. After battery disconnect and reconnect and new key, it works miles away and the keyless function works on everything now. Thank the MAN above for this.

Khan 55

If your manual key works the trunk don't bother. Its the handle itself that went faulty which is I assume the same issue with mine. It opened that one day for me when I was locked out and didn't know what to do. Thereafter it never worked again. Keep the remote above the sensor on the door handle the button, try turning the key then in the lock 3/4 and press and hold the button while trying to pull on the handle all simultaneously. Once its open just do the battery disconnect and reconnect the correct way please.


If you can gently remove the circuit board after the car is open from the remote and use electrical cleaner on it. Also clean out the remote holder as that front portion where the infra red waves are submitted through may be dirty and having slight issues.

Kotat90

Thank you so much for the response. Unfortunately, nothing worked. Since my metal/blade key did not work either, I order a new one, assuming the one in my possession was not the original one that came with the car. When I got the new key, it still didn't open the car, so I had a locksmith open it for me. the new key opened the glove, but the old key didn't. So now I think there is something wrong with he door and truck lock tumblers. what do you think?

91RS

It's possible someone rekeyed the car for whatever reason.