Key unlocks doors but wont start car
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 192
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Forums concentrate problems. Remember that many people just like you only come here when they have a problem.
Let me paint a scenario where at least some things are likely true.
You purchased this vehicle used & don't know it's history. This is why you don't have the spare key. It's possible that the previous owner had trouble. This car is an early C Class 2000, 2001 or 2002. When the C Class was a known trouble giver because Benz did computer simulated endurance testing instead of on the road. You told us you washed the engine so I will not include that. From 2003 onward these things were all fixed. Doing one's homework would have told you this. The E Class of the same era was even more troublesome.
Let me paint a scenario where at least some things are likely true.
You purchased this vehicle used & don't know it's history. This is why you don't have the spare key. It's possible that the previous owner had trouble. This car is an early C Class 2000, 2001 or 2002. When the C Class was a known trouble giver because Benz did computer simulated endurance testing instead of on the road. You told us you washed the engine so I will not include that. From 2003 onward these things were all fixed. Doing one's homework would have told you this. The E Class of the same era was even more troublesome.
Member
Joined: Dec 2011
Posts: 174
Likes: 1
From: LONDON, UK
mercedes CLK55 AMG
MY OLDER BROTHER HAD A W124 E500 AMG AT THAT TIME IT WAS A 10 YEARS OLD CAR AND THERE WASNT ANY PROBLEM WITH THAT AND I ALWAYS THOUGHT THAT MERCS TROUBLELESS CARS NOW BEEN ON THIS FORUM SHOWS THAT MERCS HAVE MANY DISADVANTAGES AS WELL. IS THE AMG CARS MUCH BETTER THAN THE NORMAL MERCS? HAVE YOU EVER GUYS HAD A AMG MERC?
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 192
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Some AMG cars are like a time bomb. They are great but tend to be abused. I would be reluctant to buy one used in SA.
Pleased your car is fixed.
Pleased your car is fixed.
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Senior Member
Joined: Aug 2008
Posts: 273
Likes: 6
From: SE PA
2001 C320
I see the forum has helped out a few others in need, as is why the reason I am in this thread too! I just did a search and came upon this thread which is almost exactly what just happened to the girlfriend while borrowing my car. She took my car today to work today and it treated her fine this morning. However, when she came out to the car this evening, she unlocked the car, put the key into the ignition, and nothing. No weird noise the car makes when you put the key in the ignition, no unlocking of the steering wheel as well. She called up in a bit of a panic. I had mentioned to her that I have never had this issue with my car before, but have heard of it (on here, on the forum) and would look it up to see if maybe there was a particular fuse she could check. As I mentioned, I have already read of THIS particular problem on the forum, so I too was a little pissed off when she told me what was going on. I advised her to find someone that could give her a lift home, as I am unavailable for a while. She called me back to tell me that she got a hold of someone, but while she was doing that, she figured she would mess around with the car for a bit. She got out, closed the door, locked it, unlocked it, got in, and guess what, it started! Great! However, my main reason for even posting-
Is this a start of a problem, or a freak accident? I plan on trying the spare key tonight, however, I don't like the fact that it did this in the first place. So, should I EXPECT for something to go bad, does it happen gradually, or just instantaneous?
Is this a start of a problem, or a freak accident? I plan on trying the spare key tonight, however, I don't like the fact that it did this in the first place. So, should I EXPECT for something to go bad, does it happen gradually, or just instantaneous?
Junior Member
Joined: Jan 2003
Posts: 17
Likes: 0
From: The Bronx, N.Y.
1998 e430, 2002 e55, 2007 Ridgeline
I had the same problem on my 2002 e55 (w210), my key did everything except start the car. It would lock, unlock, panic, trunk open,when i put it in the ignition i do hear it clicking and the steering wheel unlock, just wouldn't hear the starter attempting to engage. i took apart my key and everything looked fine so i put it back together. I did notice that i had a couple of deep scratches on the front of the key from dropping it over the years. I used a scratch pad to rub out the scratches i had on the front of IR sensor on the key. i then rubbed the front of the key on a cotton t-shirt to smooth it out. So far this key has been working fine for the past week. This is what worked for me, i was going to the dealer anyways to get a new key because this one is all beat up and it looks tired. I dont want anyone to try this and mess up their key and later get upset with me. 
Newbie
Joined: Apr 2013
Posts: 9
Likes: 0
From: Fort Worth, Texas
320 clk
I have a 98 clk320 which starts every morning just fine but once it warms up or if the outside temperature gets up it won't start. At least not right away sometimes it takes twenty minutes of turning the key on and off until it starts. Any ideas?
Newbie
Joined: Apr 2013
Posts: 9
Likes: 0
From: Fort Worth, Texas
320 clk
Thanks phister
I bought a new battery yesterday even though the one on it isn't that old and still tested good. Here are a few other issues I'm having with it.
1)When its warm and not starting I am putting the key in and turning it to the on position (at this point all the light come on just as they should) then I turn it to the start position and I get nothing or it starts, every once in a while I might get a single click.
2) Sometimes when I'm driving the blinkers won't work. In that case I usually fiddle with the key and or turn on the hazard light after that that usually start working again.
3) There are times when using the cruise control it will turn off by itself. Sometimes I can just restart it and it start working again other times it won't come back on.
Is it possible that all these are related? Also this is my first MB so I'm definitely going through a learning curve.
I bought a new battery yesterday even though the one on it isn't that old and still tested good. Here are a few other issues I'm having with it.
1)When its warm and not starting I am putting the key in and turning it to the on position (at this point all the light come on just as they should) then I turn it to the start position and I get nothing or it starts, every once in a while I might get a single click.
2) Sometimes when I'm driving the blinkers won't work. In that case I usually fiddle with the key and or turn on the hazard light after that that usually start working again.
3) There are times when using the cruise control it will turn off by itself. Sometimes I can just restart it and it start working again other times it won't come back on.
Is it possible that all these are related? Also this is my first MB so I'm definitely going through a learning curve.
MBWorld Fanatic!
Joined: Jul 2008
Posts: 1,005
Likes: 0
2013 UFO
Thanks phister
I bought a new battery yesterday even though the one on it isn't that old and still tested good. Here are a few other issues I'm having with it.
1)When its warm and not starting I am putting the key in and turning it to the on position (at this point all the light come on just as they should) then I turn it to the start position and I get nothing or it starts, every once in a while I might get a single click.
2) Sometimes when I'm driving the blinkers won't work. In that case I usually fiddle with the key and or turn on the hazard light after that that usually start working again.
3) There are times when using the cruise control it will turn off by itself. Sometimes I can just restart it and it start working again other times it won't come back on.
Is it possible that all these are related? Also this is my first MB so I'm definitely going through a learning curve.
I bought a new battery yesterday even though the one on it isn't that old and still tested good. Here are a few other issues I'm having with it.
1)When its warm and not starting I am putting the key in and turning it to the on position (at this point all the light come on just as they should) then I turn it to the start position and I get nothing or it starts, every once in a while I might get a single click.
2) Sometimes when I'm driving the blinkers won't work. In that case I usually fiddle with the key and or turn on the hazard light after that that usually start working again.
3) There are times when using the cruise control it will turn off by itself. Sometimes I can just restart it and it start working again other times it won't come back on.
Is it possible that all these are related? Also this is my first MB so I'm definitely going through a learning curve.
Newbie
Joined: Apr 2013
Posts: 9
Likes: 0
From: Fort Worth, Texas
320 clk
The check engine light did come on for a little while last week. (See pic) I scanned it, it came back as an O2 sensor. My daughter had put a low grade fuel in it. I filled it up with super and ran it for a while. The next time I got in it the check engine light was off.
Newbie
Joined: Feb 2013
Posts: 14
Likes: 0
200 C200 Kompressor W203
Hello all, thank you for this informative thread. The secondary power-up coil in my key
has broken, and like everyone else, is not working the ignition. Are there any electronics gurus who might know where I could source this coil? so to have replaced?
Thanks, John
has broken, and like everyone else, is not working the ignition. Are there any electronics gurus who might know where I could source this coil? so to have replaced?
Thanks, John
MBWorld Fanatic!
Joined: Nov 2001
Posts: 5,851
Likes: 196
From: Huntington Beach, Ca.
'17 Jaguar XF
Newbie
Joined: Jul 2013
Posts: 5
Likes: 0
E320 2004
Btw names Kerwin, Pleasure.
Newbie
Joined: Jan 2014
Posts: 1
Likes: 0
BMW X5
repair help
Try this test. Turn on your cell phone camera and point the red window in the nose of the key at the camera lens. Press and hold the lock or unlock button. Does the led inside the key illuminate? If yes, the RF and infrared portion of your key is fine. If the doors unlock with the key, then the EIS thinks it is your key.
The system is designed so that you could have a bad key battery, and still start the car. You can open the door with the cut metal key inside the key assembly. Inside the EIS there is a transformer primary. The secondary is located inside the key. When the key is inserted in the dash an AC voltage is connected to the primary. Inductance carries the current into the secondary in your key. The current is rectified and used to power the key to turn on the LED that you saw when pressing the buttons. Since your other key works, we can assume that the EIS in the dash is fine. If you saw the LED with your camera, the infrared transmitter is fine.
The problem lies in the secondary of the transformer in the key. The secondary is a coil of wire wrapped around a powdered iron core. Aside from the battery, it is the heaviest item in the key. It is most likely to be jarred lose when dropped. Use a 10X loupe to examine the circuit board. Look for the inductor in the nose and be sure it is well soldered. Simple to fix but you need someone with a surface mount soldering station. Good luck!
The system is designed so that you could have a bad key battery, and still start the car. You can open the door with the cut metal key inside the key assembly. Inside the EIS there is a transformer primary. The secondary is located inside the key. When the key is inserted in the dash an AC voltage is connected to the primary. Inductance carries the current into the secondary in your key. The current is rectified and used to power the key to turn on the LED that you saw when pressing the buttons. Since your other key works, we can assume that the EIS in the dash is fine. If you saw the LED with your camera, the infrared transmitter is fine.
The problem lies in the secondary of the transformer in the key. The secondary is a coil of wire wrapped around a powdered iron core. Aside from the battery, it is the heaviest item in the key. It is most likely to be jarred lose when dropped. Use a 10X loupe to examine the circuit board. Look for the inductor in the nose and be sure it is well soldered. Simple to fix but you need someone with a surface mount soldering station. Good luck!
Hi Moviela, I am trying to repair two keys on my dads c320 both dropped and both with broken induction coils. exactly the same as the pictures submitted by others early on in this thread.
two questions:
1) we have lost one of the broken induction coils, can i buy this component? from where?
2) the second key coil has come off the circuit board and im happy enough to solder back on, but do I need to reattach the red coil wire to each point of the solder as seen in a picture I found on the web below. if so, how can I do this?
http://s463.photobucket.com/albums/q...BKeyCoil01.jpg
Newbie
Joined: Aug 2015
Posts: 2
Likes: 0
e320 1999
remote info
I recently dropped my keys (as I have many times before) but right after this drop, they keys wont start my car anymore. The remote lock/unlock works perfectly, but when I insert the keys into the ignition, there is no whirring sound and I cant turn the switch either.
Ive dismantled the key and nothing is loose/broken.
Im surprised that the door lock/unlock works while the ignition doesnt. Anyone know which part of they key is responsible for ignition?
I have a spare key so Im OK for now, but Id like to get this fixed in case I drop my second key..LOL. Ill try to get pics up soon...meanwhile anyone been through this before?
Thanks.
Ive dismantled the key and nothing is loose/broken.
Im surprised that the door lock/unlock works while the ignition doesnt. Anyone know which part of they key is responsible for ignition?
I have a spare key so Im OK for now, but Id like to get this fixed in case I drop my second key..LOL. Ill try to get pics up soon...meanwhile anyone been through this before?
Thanks.
