key fob

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cooks

Active Member
Joined
Jul 23, 2010
Messages
211
Location
West London
Car
W124 Coupe,TREK Bike
I tried to lock the doors and windows with button held down on my key fob but nothing happened,have i knocked the sensor or does the fob need reprogramming.This was working..any advice.
 
Can you describe the type of fob that you have?

Dec
 
I tried to lock the doors and windows with button held down on my key fob but nothing happened,have i knocked the sensor or does the fob need reprogramming.This was working..any advice.

IR sensor common failure

Needs 2 joints resoldering
 
its 95 model with the black key fob with the red sensor,the key is opening the doors but not shutting everything when the windows and sunroof are left open.
 
So, the remote fob button will lock and unlock the doors but won’t close the windows/sunroof when locking, is that correct?

Was the car battery disconnected recently?

Dec
 
Hi Dec the battery has not been disconnected ,i had all the windows down and sunroof and and held the button on the fob facing the driver door handle to shut every thing but nothing happened..so i am wondering does the key fob need reprogramming..
 
Did you try reprogramming the windows auto close by closing each window and holding the window button down for a few seconds?

Did you try new battries?

To program the one button flip out remote do as follows;
-unlock car with remote
-turn key in ignition within 30 secnds.
-remote now programmed to car.

note;this wont work if the remote wont lock or unlock the car so maybe remote batteries need replacement or a faulty remote fob button.

Dec

KeyfobAndBatteries.jpg


edit;Programming is also called Synchronizing System

254686d1250492789-programming-keys-sync-system.jpg


Also, might be a poor contact on a fuse relating to the central locking; try twisting the fuse in its holder.
 
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Iv just checked the batteries seem to be fine.tried to reprogram but with no joy..
 
If you look through the view finder of a digital camera can you see a Blue/White light flashing when you press the button?
The Red lens will illuminate and then you will see, or should see, the Blue/White light flashing when you press and hold down the button, can only be seen through a digital/phone camera.

See...https://www.youtube.com/watch?v=jt7ZO5Ya0kY

Dec
 
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i had this issue with my old key...i did manage to solder the old one aswell as getting a new one from Mercs.
 
I wonder if the close all function is related to the alarm; do you have a working alarm?

My old w202 of 1995 would close the windows if the were open when locking, this was part of the alarm system.
What were you doing immediately before the fault appeared, were you doing any work on the car?

Dec
 
I was at a car show last Sunday,i tried to shut everything by holding the button on the fob to show another person but for some reason it didn't work.However i did wash the engine the day before...
 
i also checked the infra red on a camera lens and that is flashing like it should ..
 
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the link you sent me on how to check the infra light on the key fob,it says to look through a camera lens which i did and the white flashing light in the fob is working.As i was at the car show i had the windows and sunroof open,i was showing another person with w124 that i could lock all the windows and sunroof by holding down the button the fob to close everything on the car..but nothing happened.
so i assumed the key needs to be reprogrammed.
 
i haven't checked the fuse box you could be right..ill check..
 
You may have to remove the fuse cover as illustrated in the picture below, of a W202, to get at the wiring below the fuses.

Dec

N101.jpg
 

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