Remote Key Fob Not Working (1996 - C200)

[jayb]

Has anybody had any problems with remote key fobs not working? I've tried replacing the batteries and it still didn't work.

Although this key fob is only a spare, I would like to get it working if possible, just in case!

Is there a safe/easy way to dismantle the key fob, so that I can check that the button is working and there are no damaged connections on the circuit board?

Cheers,
Jay

 

[television]

Try re-set point control tranmision port to drivers door and press lock or unlock button for a few seconds

Malcolm

 

[maddog]

Has anybody had any problems with remote key fobs not working? I've tried replacing the batteries and it still didn't work.

Although this key fob is only a spare, I would like to get it working if possible, just in case!

Is there a safe/easy way to dismantle the key fob, so that I can check that the button is working and there are no damaged connections on the circuit board?

Cheers,
Jay

I had one replaced under warranty according to the service manager its not uncommon

 

[MondeoMan]

You have tried the reset procedure, I assume? When mine broke, I couldn't find a way of opening it up without breaking it. Others have had problems with the battery contacts, do these appear sound?

Now for my favourite tip - if you view the key through a phone camera, you can see the IR flash when you press the button. Mine didn't work, despite passing the battery test. Replacement is £120, takes around 5 days, and you need proof of ID.

 

[jberks]

Failures are common but we've revived ours several times with new batteries and a resync with the car's system.
I can't remember the resync sequence but its something like ignition on-off, fire key at the mirror, then ignition on again - but someone will be able to give the full process.

 

[GarethR]

Failures are common but we've revived ours several times with new batteries and a resync with the car's system.
I can't remember the resync sequence but its something like ignition on-off, fire key at the mirror, then ignition on again - but someone will be able to give the full process.

I bought a new spare remote for my car (W202 C230K).... then found the re-sync procedure in the car handbook under "Driving Authority System", not in the security system manual.

SYNCHRONIZING LOCK SYSTEM
Aim the transmitter of the remote control at the receiver in the interior mirror and press transmitter button briefly twice.
Turn the key in the steering lock to position 2 within about 30 seconds.

 

[mykidmercedes]

Now for my favourite tip - if you view the key through a phone camera, you can see the IR flash when you press the button. Mine didn't work, despite passing the battery test. Replacement is £120, takes around 5 days, and you need proof of ID.


Mondeo man, i have a w202 switchblade type keyfob. My red light works ok, what should i see with the phone camera test ? ( Should i see anything else in addition to red light?) Thank you.

 

[severn]

Now for my favourite tip - if you view the key through a phone camera, you can see the IR flash when you press the button. Mine didn't work, despite passing the battery test. Replacement is £120, takes around 5 days, and you need proof of ID.


Mondeo man, i have a w202 switchblade type keyfob. My red light works ok, what should i see with the phone camera test ? ( Should i see anything else in addition to red light?) Thank you.

A nice picture of a key

 

[leftymark]

Merry christmas everyone, not so merry in my case i'm working and my car has died, i shall explain-
i have, like jayb, a 1996 C200 with a single button key fob. i went to de-activate the alarm and nothing happened. This has happened before and as you say i changed the batteries and did the resync and everything was fine. this time i got into the car manually setting off the alarm, changed the batteries, resync and the engine started and i drove home. when i stopped i couldn't activate the alarm, now when i press the fob nothing happens. The green and red lights flash in the mirror when i try to start the engine the engine turns but is still immobilised and thats it! The resync does nothing.
For quite a few months i have had to stand right next to the car to get the alarm to activate/deactivate. (i don't know if this is normal)
I have tried mondeoman's trick with the phone camera and i cannot see the red light in the fob, my mechanic has told me that it is normally the mirror at fault.

buying a new fob is expensive, so i would be happier if anyone has anymore diagnostic tricks that would confirm whether it is the fob or mirror and doesn't involve putting the car into a MB dealership, or a way to inop the system so i can at least get the car back on the road.

Any help would be greatly welcomed.

 

[television]

Number one, everyone should have a spare key,and the spare should be used for the next operation, without makes it harder.
Disconnect connector from IRC module or disconnect neg on battery for 10 secs. then press key on remote max 100 times. do another re sync with key, re code radio if necessary, if it continues to fail install IRC control module with modified software, same part number marked with white dot,in use sinse 22-07-96

affected vehicles with redesigned RCL control modules
210 820 27 26 (can)
210 820 28 26 8PWM.
This all work in conjunction with radio, without spare key, who knows if it is the key fob

Malcolm

 

[jberks]

I have tried mondeoman's trick with the phone camera and i cannot see the red light in the fob, my mechanic has told me that it is normally the mirror at fault.

I have to disagree with your mechanic. I've come across many dead remotes but virutally no 'car' failures. I'm sure they happen but are far rarer.
The reciever in any digital camera picks up infra red signals. Test it out with your TV remote, you'll see the LED flashing. If you can see the one on your TV remote but not your key, that's a good indication that the remote has failed. You should also see a visible red led in the remote too - does that come on? I have had a couple of remotes replaced because the buttons failed.

 

[leftymark]

Thankyou all for the help, it does appear to be the remote that has died so i shall go to the dealer and order a new one. thanks again

 

[philharve]

Hi All

What is there in the remote that can die, apart from the battery?

REGARDS Phil

 

[anyweb]

Hi All

What is there in the remote that can die, apart from the battery?

REGARDS Phil

the button on the key fob itself

and this is how to fix it

http://forums.mercedesclub.org.uk/showthread.php?t=26895

 

[gsc]

Is that the re-sync procedure, click door open button stwice then insert ket into position 2? what is position 2, ignition lights on?

 

[taylor172]

1997(R) C200: Alternative key re-sync procedure - TRY THIS!!

Hi Peeps. Just smarming to myself after two nightmare days of key trouble, so thought I'd share this re-sync method with you. I have the 3 button 'long' keys, with the sliding/removeable metal key at the side (Elec key part no. 208 766 02 06 / Emergency Key part no. 208 766 08 06).
Long & short: drove car with weak battery on a few consecutive short runs with all the kit switched on. Got out & tried to lock with remote - nada. Tried to charge battery - still nada. Friend brings brand new car battery from his garage - still nada. Collected emergency (Flat) key from home. Car will start with emergency key & central locking works with dashboard switch & also does the lock/unlock taxi door impersonation when driving/parking. That being the case, all is OK with car, so must be the key, or the sync between car & key.
Have tried all the re-sync tips found on this site - special thanks to Malc Television - when do you find time for your own life matey? Suggestions mostly involving pressing buttons in various sequences & turning ignition to position 2; no joy - ignition/immobiliser will not even allow key turn.
Garage friend visits all his electrical, diagnostic & key colleagues around town - conclusion is the elec key is fine, so must need to be re-sync'd, or code is lost. They said it couldn't be done...
Did I say this tale was short?
I'm not the type to 1) give up easily; 2) spend £150-200 at a main stealer for a bit of plastic; 3) listen to common sense when I hear it.
At this point, I went for the 'try whatever comes into your head' method & hit the jackpot - even my No. 2 elec key (which I thought was knacked & only kept for the metal key bit) works now!!
TRY THIS FOR SIZE:
1. Put the elec key in the ignition slot
2. Press the open & close buttons in turn - you should find that the second press makes the doors lock or unlock
3. Take the key out & re-insert it - you should hear the satisfying clunk of a happy ignition
4. Start the car & enjoy!!!!
I cannot guarantee it will work for you, but it sure did for me. I have been happily clicking ever since - I'll probably flatten the battery again...
From now on, I have promised myself:
- I will rotate my electronic keys, so they maintain their charge & sync
- I will never be afraid to try something - even if a garage mechanic tells me I'm wasting my time.
Be good - drive safely & be kind to each other.
Peace & Love (til the next time it lets me down...)
Chris

 

[television]

Thank you and welcome.

The method you used was almost the same as for doing the ML with RF locking only, with the exception of putting it back a second time immediately.

 

[Passionheap]

Button Key Fob

Taylor172. Many thanks for your useful tip. My fob has been playing up for a few weeks now and on Thursday would not make the usual 'noise' kept trying and it started. Got 2 new batteries from Tesco CR2025 £3.49! drove home and inserted them. Went to car and it wouldn't work. Rang Mercedes and they advised I'd need to buy a new fob £219.00 or £235.00 with a new key (which I don't need) and then get the car to their workshop and they would re-programme the Fob and the EIS (electronic Ignition System) How much would that cost?? You have saved the day so once again many thanks. I'll now search eBay and bid for the many that are on offer,prices range from 99p to £27.00 so wish me luck! I'll never let this happen again.
Regards,

 

[taylor172]

Power to the People

Hi
Glad to hear it worked.
Happy Merc-ing
C