Blown fuse in the rear view mirror sensor – may be

[bernardtam]

Dear All,

My fob key can’t open the central locking system in the car – W202 1997 C230K. I’d change 2 x CR2025 – 3V new battery in the key, still doesn’t work. I use the key to open up the boot ( open up easily ) and check the car battery and it is good. Tried to open up the driver’s side door manually but it seems that I couldn’t do it as I am afraid that I will break the key !

I am thinking that the sensor’ fuse is blown but how can I open up the bonnet manually and get to the main fuse box ??

Or if the fob key can open the door manually definitely, then I think I can open up bonnet easily once I can get into the car !

Any suggestions and advises for me ???

I tired again to open the door manually but again, not able to do that !

Thanks guys

Bernard

 

[bigasotonuk]

Hi,
I take it you have no spare fob key? You have the batteries the right way round (don,t mean to insult you).
Your fob maybe broken try this link it is a "HOW TO" showing a repair for this type key
http://forums.mercedesclub.org.uk/showthread.php?t=26895
There is a method of re-synching to but you,ll have to turn the ignition on for this but as you can,t get in at the moment try the repair first.
I will say though that my lock on the c230k is very stiff so it might be worth trying a bit of release oil and working the key in and out of the lock. But do remember that the alarm will still be armed and has battery back-up.
Let us know how you get on.

 

[bernardtam]

Hi Andy,

Thanks for your quick reply !

I tried both of the fob keys I have and both of them are working in good condition 2 days ago. The new battery is in correct direction and I can see both keys emit the infrared light when I press on them.

Are you saying that the fob key can open the door manually 100% for sure ?? If so, I will try to lube the lock a bit and try it again !

It is strange that I don't think I have the Alarm in my car or it never report to duty at all since 1997

Thanks - Bernard

 

[bigasotonuk]

I also have a 97 C230K and the key blade on the fob fits every lock on the car boot, passenger door, ignition and glove box.
Have you not got folding seats on yours? as you could fold down the rear seat and climb through to the front to open the door and flip the bonnet open.
I have only heard my alarm when it went wrong.
The siren is fitted on the passenger side under the bonnet just behind the radiator, and should beep though very quietly when you lock and unlock the car
If you manage to free the lock the car will still be immobilised by the alarm.
Sometimes disconnecting the car battery can clear the fault but bear in mind that the alarm may sound.

 

[bernardtam]

Hi Andy,

I already disconnect the grounding wire in the battery for half of an hour to allow the computer to reset but it didn’t work in my case.

I don’t have folding seat in my back seat and so, I’m afraid that try to open up the driver’s side door manually is the easiest way to open up the door then the bonnet can be opened in no time.

Thanks - Bernard

 

[bernardtam]

Hi Andy,

I just went down to the garage and tried again. I use both keys and both can lock and unlock the boot easily, while when I tried to open the driver’s side door, I can feel that I’m going to break the plastic case if I turned it further a bit more. This is also for both of the key.

Well, I think I will try to open up the bonnet from outside then check the fuse for the rearview mirror remote sensor ! But anyway, I don’t understand why the fuse blown after I locked the doors, it doesn’t make sense to me. Well, may be there is something else wrong with the car !!

Thanks - Bernard

 

[bernardtam]

I just posted a new thread and would like to close this one - Thanks Andy