KeyFob Issue working kind of...wierd

[rossy]

Hi all,

Not been on for a while which is kinda good news....coz I gerneral only come on for help

Anyway...nice day so thought I'd take the Beast out for a Run.
2006 CLS 55 AMG

Fired up no problem got her out of the garage...waited for the (Bat Convenience warning to got off) (new batteries last year...both)
Come to lock it and realise I left a window open....would not close with the key....then it would not unlock the car? (red light flashing on the key fob tho) but as I have some spare CR2032 thought I'd change anyway as the car gets very little use sadly.
Made no differance.
But I've noticed that if I hold the key very close to the drivers door handle only it works (tho even thats intermittant??

Would not mind but was only talking about gettingg another key the other day as I've only ever have one key with it.

Any thoughts?

Thanks
Rossy

 

[whitenemesis]

What you describe is the RF failing and the key only working via IR and the little sensor window in the driver's door handle.
Get the codes read, see if the car antenna amplifier is failing.
Intermittent IR operation is very common as the sensor is prone to wet and the sensor window becomes obscured.This is usually witnessed by poor operation of the Convenience (summer) opening function.

 

[rossy]

Windows/Sunroof open and close via IR as they should.....where can I find "modules" to do with RF?

 

[Dizz]

I’m sure you know you own key batteries requirements but is it cr2032 and not cr2025?
The 2032s are a little bit thinner and would still fit but the connection might be a bit hit and miss, also did you clean the contacts in the key?
As I say this is probably a red herring for you, but worth a mention..


Sent from my iPad using Tapatalk

 

[rossy]

Not sure I understand they are CR 2032 as stated in 1st post....its a new key for my car (I.e. has the chrome down each side (apparently it should not be this key) but Merc Dealer said its fine. Its what came with the car so guess a previous owner had it programmed. I got the blade at Dealer as it had a blank in it!! I going to get a "full" new key from Merc...last time I checked £265 or there abouts.
Will see what that does....i.e. if that works then I have a faulty "current" key. If it works the same as my current then theres obviously an isse with the key reciever on the car.
Radio works Fine....both AM and FM (other posts say if the amp goes there is no AM and very poor FM) not sure if this applies to my 2006 AMG CLS 55 or not....
Tipical that it happens as the good weather (or better) is due....I keep it on the road all year round...but it only realy gets used summer......its been fine all winter on the few days I've used it just to give it a run...

 

[rossy]

WOW this seemed to work....(I'm from an IT Background) I wanted a way of checking the Remote Frequency side....we know the IR works.
You can turn your MOBILE PHONE into a key tester.....(only tests not program)
If you can get hold of a Realtek 2832U DVBT USB dongle (like dirt cheap of that e auction site) and Micro to USB adabptor (Which I happed to have) you download the Android Drivers for the USB dongle then search for QuestaSDR.
The only thing it took a while to sus out was on the frequecies you need to be in the 433mhz range in uk and 315mhz in US I believe?
Anyway when you open the app at the top it will start at 100mhz....there are arrows at the bottom for up and down.....but this takes ages and then I realised....in front of the frequency is either a U or a D (you can toggle this via touch screen....U is up and D is down......Duh I know but did not have instructions....you can then alter each number in the frequecy so ....with U I tap 1 3 times to get to 4....1st 0 3 time and 2nd 0 3 times..
I them used my Nissan key which I know to work and you can hear (white noise) via the speaker on the phone....you realy need to be somewhere quiet for this....because the fob could be any frequency arounf 433 you will need to listen and watch the frequecy measure....you can then when you find it using your finger slide the vertical bar right on it and you'll hear it!!!
So once I got the hang of it...tested the Merc key.....no RF output at all....
I even checked the Wifes BMW key in the 868mhz range and found that......so...kinda good news that I think its just the key.
Is there a way of re-syncing the key? i.e. could it be that its forgot?
I've seen some things about putting in the ignition holding down lock then press unlock 5 times etc etc blar blar....not sure if these are TIME WASTERS on line or actual things you can do???
If so what the correct way for my car year etc.....or would as I expect, it still broadcast a frequency anyway ???
Umm.....

 

[rossy]

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This is the old version of the app but shows you so you get the idea!!

 

[rossy]

Heres the app
https://play.google.com/store/apps/details?id=com.sdr_labs.questasdr&hl=en
Heres the Driver I used
https://play.google.com/store/apps/details?id=marto.rtl_tcp_andro
Heres the DVB-T reciever (yes you can watch TV via earial on your phone after.....
USB Digital HD TV FM Audio DVB-T2 R820T RTL2832U Radio Recorder Receiver Stick 8094983354047 | eBay
Micro USB to USB adaptor
Micro USB Cable M Host to USB F OTG Adapter Android Tablet Phone PDA Samsung HTC | eBay

This is the app...but does not show using to test key....but at least you can see what I descibe to do above.....

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[Carlos2k]

My CLS has this issue now and again... go to lock or unlock it and it literally does nothing... mini panic! Hold it near the car and then it unlocks. Weird.

So you think its the key?

 

[whitenemesis]

Not weird, simply the switch from long range RF to close range IR.
Sounds like your RF function is failing. Could be the RF coil in the fob or the antenna amp in the car. Can you try the spare key?

 

[Carlos2k]

I'll change keys and see if it does it again

 

[rossy]

Yeh mine appears to be the Key...its the only one I have and was planning to get another From Merc Dealer now anyway....so will order that and test....if its the same I know its the car but bet it works.
The Key I have is not the correct one for my car....its for the later Model.....but I checked with Merc Dealer and they said its fine....but it still looks like thats whats failed to me....maybe its a copy? i.e. not gen Merc...we'll see.

 

[Terryk]

hi to all, I have the same issue with my very recently purchased w219 2006 m113.
I will try to put every incident in an order to give you a better image of the whole matter since I need every possible assistance and idea.

I purchased the car few days ago, Saturday afternoon. Previous owner did not use the car a lot (company van and two other cars in household) and also told me that second key might need batteries.

1. When parked home on Saturday I noticed that one key could not lock the car (although same key could unlock it). I did not pay attention on the matter. Also I noticed that I couldn't hear any beep sound from alarm when locking or unlocking.

2. same day, few hours after my purchase, I noticed that I was able to unlock the car by having the keys in my pocket and by touching the rear door’s handle. This keyless unlocking action could be performed only when using read doors' handles. I remembered that when checking the specific car with a vin decoder, I saw that it has keyless go, a function that previous owner never used when I asked him and he did not have a clue. He also claimed that he had never used the engine start button located on the gear shifter-lever.

3. next day on Sunday and after a short driving of 15miles I spent about 6 hours cleaning the whole interior of the car so car was unlocked all this time and used quite a lot the front electric seats to move them forward and backwards. When finished cleaning I again realized that one A key could not lock the car, although same A key could unlock it (The second B key could perform both functions). I then noticed that this specific problematic "A" key fob had the lock button de-shaped so I concluded that probably is the button itself that has been broken and cannot unlock the car so I have to replace the key fob case with a new one (ordered a new key fob case and received it today). I locked the car with "B" key and had dinner and then, after one hour, I drove the car again for a 15miles driving and parked it and left it till Tuesday night, again locked using "B" key.

4. Tuesday night I received the new engine oil dipstick so I went to the car with the problematic "A" key fob, I unlocked it, I turned the ignition to 2nd position (battery etc but not engine running) and left it there for about 5-10’ while I was placing some stuff in the boot. I also tried to start the engine by pressing the engine start button located on the gear lever just for testing/fun but nothing happened (key fob was in ignition in position 2 but I think you should not place the key fob in ignition because this will take priority from the start button).
When I decided to return to my flat I tried to lock the car but, of course, the problematic "A" fob did not lock it. I remembered that you can lock the car by pressing the lock button in the boot lid. So I went back to the boot, I opened the boot and pressed the lock button located on boot lid. Boot lid started to moving down but after half the distance it went back to full open position and an electric "cancellation" noise was heard. I pressed once more the lock button of the boot and again it went half way down and then returned to fully open position with same electric "cancellation" noise from the system.
So, I realized that this wont work and decided to go back to my flat. I locked the car using the second "B" key fob from a distance of about 15m.

5. Wednesday afternoon I grabbed the second “good” "B" key fob and went to the car to perform some works on it (adjust my wipers’ arms and check oil level and most important oil quality-colour with new dipstick. I have received oil+oil+air+cabin filters yesterday so the plan was to service the car this Saturday). For my surprise the good "B" key fob did not unlock the car and saw that red led indicator on the fob did not light.

I bought 4 new 3V cr2025 batteries and replaced the batt of both key fobs. Again none of key fobs were able to unlock the car.
Now both key fobs’ red led is lighting when I press a button but car does not respond at all.
Also, using my mobile’s camera, I checked the infrared of both fobs and both look fine so my guess is that both key fobs respond but there is no reaction from the car.

6. Today I went to driver's door and tried to open the car by sticking the fob very very close to IR sensor of the door handle but again nothing happened. I can say that after 10 times I pressed the unlock button I am 99% sure that I hear some noise from the door lock once! but only once! again nothing happened.

I am thinking of using the steel blade key to unlock the vehicle and have a look in the boot for blown fuses. Thing is that I am not sure if this will trigger the alarm. Although as I said above I never heard the alarm arming or disarming when locking or unlocking and I am not so sure if it has been armed now (with vin decoder the car came with factory fitted alarm but thing is I am not sure if it works).

I have read that if it is not a blown fuse, it may be the antenna receiver or the cabin control module. Is this different from the keyless go control module? Or vehicles with keyless function have one module for both functions (unlocking-locking with key buttons and also by touching the handles).
I see that it is a bit of a common failure but has 3-4 different reasons without clear differences between them for an inexperienced person.

Apologies for the length of this post.
Every idea and assist is very much appreciated, since I don’t have experience with merc.

 

[rossy]

My CLS has this issue now and again... go to lock or unlock it and it literally does nothing... mini panic! Hold it near the car and then it unlocks. Weird.

So you think its the key?

This is why I did the RF test on the FOB.....it looks for me like it the FOB not transmitting RF but it is transmitting IR....you need to do what I did, trust me it will be cheaper than getting Merc Dealers or even an indi to check.
A replacment key (which I need anyway) will be cheaper than fixing an RF reciever issue on the car.....very little on line on the CLS but it seems its in the roof at the back window.
Web says if the 7.5 amp fuse in the boot (I believe fuse number 8) is blown you would also notice very poor radio signal as shares the same AMP....mine is fine so if its not the key I think if it was broken wire etc it would work if I put the key very close but it does not.......I'm 99% confident mines the key......time will tell and I'll update the post.

 

[Terryk]

Small update from yesterday's and today's tries:
as said, yesterday I went to driver's door and tried to open via IR with no results.

Today, the blade steel key does not unlock the door (I tried both of them).
Eventually I decided to open the boot using the blade key and I checked fuse no8 7.5A but seems ok.
With a A/V tester I checked battery's status and is only 2.4V !!!
I know engine wont even start below 11.5V so 2.4V is way too low.

Next step, I will use jumper cables or battery booster to see if this helps.
It is very strange that the blade keys did not open the driver's door (although they open boot lid).
Thanks

 

[Terryk]

I believe lesson learned.
with jumper cables the car unlocked using the key fob. After two minutes engine cranked (with an effort and in parallel lcd screen lost its illumination for half second). Battery was dead and caused all this mess (again very strange that the blade keys did not open the driver's door with a dead battery).
I am charging the car at the moment but I do not know if it will be sufficient. Worst case scenario I will buy a new 019 type battery.
Could not be more happy