w209 clk270cdi remote central locking intermittent

[malphadour]

This week my so far trusty clk has decided to push my patience to its limits.

Firstly at just the wrong moment the remote central locking decided to pack in and i then discovered that the key on the drivers door doesnt work.

I got in thru the boot and started pulling fuses and relays out of the box (the one on left side with black polystyrene cover) and after a bit i got flashing lights and the remote started working. Got to my destination and could not lock car....more fuse pulling resolved temporarily.


Since then it is getting worse to the point where no matter what i do it wont lock or unlock........and then six hours later it works fine. I have two remotes and now it refuses to respond to one of them at all whilst the other is working on and off.


And today i lost the turbo...no idea now if my fuse pulling Frenzy has caused an ecu reset or something to kill the turbo or if that is just a really annoying coincidence.


So, central locking remote _ replacement relay or something more involved/expensive.

As a note, i had the alarm disabled when i bought the car becuase it constantly malfunctioned _ maybe related?

 

[Dec]

Start with the remote batteries, replace them if the havent been changed recently, ensure the Red LED lights up when you press a button.

Try holding the remote very close to the drivers door sensor when you operate the button.

Is your key the same as the one in video below?
What year is car?
How was the alarm disabled, was it unplugged or was a fuse removed?

Dec
[YOUTUBE HD]r4VbN4nOvkM[/YOUTUBE HD]

 

[malphadour]

remote

Hi;

I replaced the batteries in both remotes about a month ago

i had never noticed the red led ............. one of them is not working at all....the other one lights up fine...so that is part of the mystery

I have been using the working one this weekend but it is still intermittent

Regarding the alerm....i don;t know exactly how it was disabled and the chap who did it is long gone


yes to the key in vid and it is a 2003 model

 

[Dec]

The remote locks and unlocks with both RF and IR and picks up the RF signal (Radio Frequency) from the remote via the heating elements in the back window – top two lines I think – if the RF fails then the car can be opened with the IR (Infrared)
The remote needs to be 2mm from the sensor in the door handle for the IR to work.

Do all 3 buttons fail to light the Red LED on the faulty remote?

Dec

Picture source… 04 CLK 320 Door Sensor HELP?! - Page 2 - Mercedes-Benz Forum