Still having issues with keyfob, any ideas!!!

[markm730]

Ive had issues with my keyfob over the last 4-5 weeks whereas it stopped operating to lock / unlock my car. Im currently using the emergency key for locking at the moment Ive put a few posts up previous for any help but to no avail. One other member said he had a similar problem and sent his key fob off to a company on eBay that repairs them. This I have done, at a cost of £40, all be it cheaper than it would have been going to Mercedes!, and just got it back and hey presto - still the same, has a nice new case though!
Its had new batteries and the light is working when buttons are pressed and have also tested to see if the beam is working aswel.

I thought it may have been a fuse so have checked all my fuses and they are fine.

Does anyone know what actually receives the signal from the remote to lock / unlock the car and is it acessible?

Im all out of ideas now so any help would be much appreciated.
Thanks in advance

 

[pmcgsmurf]

If the spare key works and the repaired one does not can't you just send them it back and tell them this?

 

[markm730]

If the spare key works and the repaired one does not can't you just send them it back and tell them this?

Sorry, forgot to put this down, Both keys have the same issue.
One of the reasons why I think it may be something inside the car

 

[Teego]

Think you need a good auto-electrician.

 

[pmcgsmurf]

A bit weird of both keys do the same to try and one fixed!

What has the diagnostic scan shown up?

 

[Jobsworth]

Has your radio reception become poor since this fault appeared?

 

[steveskeggy]

Did you check/change all of the fuses?
Looking on the tinternet, I found a fuse diagram.
Look at 21, 22, 32, 33,57, and 41 (This is listed as central locking interior switch, but its worth a check)
There is also a bunch of fuses for convenience locking (Soft close?) anyway apart from the ones listed above they are 8 and 9
Fuses 1 to 20 should be in the boot, 21 to 42 should be under a cover on the end of the dashboard, probably the passenger side, open the door you will see a cover on the end, prise it off gently and the box should be under there.
fuses 43 to 65 should be under the bonnet, one side or the other.

Some cars can have a relay that serves the door and the boot locks, have a look on your fuse diagram see if locks are mentioned under the relay diagrams.

Have a look at this:

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Good luck

 

[markm730]

Has your radio reception become poor since this fault appeared?

bizarrely yes it has. ??

 

[markm730]

A bit weird of both keys do the same to try and one fixed!

What has the diagnostic scan shown up?

I had a breakdown recovery guy come out last week and he plugged his machine in and said nothing was showing up

 

[Jobsworth]

bizarrely yes it has. ??

I would say your aerial amplifier is the problem. It does both the remote locking and the radio aerial.

 

[markm730]

I would say your aerial amplifier is the problem. It does both the remote locking and the radio aerial.

ok, maybe getting somewhere....
where is it located and is it easily accessible?

 

[Jobsworth]

I've not done one on the coupe. It might be in the tailgate, near the top of the glass. A check of the wiring in the hinge might be a good place to start.

 

[markm730]

I've not done one on the coupe. It might be in the tailgate, near the top of the glass. A check of the wiring in the hinge might be a good place to start.

thanks for that, I'll have a look at weekend when I get chance.

 

[91dm]

Have you checked the alarm module on the passengers inner arch? A quick google will show you the exact location.

 

[markm730]

Have you checked the alarm module on the passengers inner arch? A quick google will show you the exact location.

will do, thanks for that

 

[Sicario]

This may have been answered in here somewhere but i just wanted to add a solution to this problem.

Check fuse no 8 in the boot, if thats ok, change battery in the key-fob, if still nothing then the solution lies in changing your antenna booster amplifier. The car uses the rear window heating element as the aerial for your radio, and also the receiver of the signal sent from your key-fob, if the antenna booster is kaput then it needs changing or at-least the wiring/power supply to it needs checking. The booster can be found in the passenger side (same side as the fuse box in the boot) rear c pillar behind the triangular trim that sits flush with the parcel shelf, i just needs a good tug and it will un-clip.