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My drivers side isn't working and I couldn't find one in search. Thanks!

Sergey_

This part number is A2037602377. It includes IR sensor and mechanical lock for only your keys. W/o DIY you can get it only from Mercedes service after typical anti-thief formality. If you can work with solder iron, then remove this part from car's door and replace or repair IR sensor. All you need is torx20. Unscrew one torx20 screw in inner door side deep hole under door's rubber and remove part carefully. It connects to door's control module with 3-pin connector. Then you must cut metallic tooth for IR sensor removing. Now you can try to repair IR sensor. Carefully remove transparent mastic near outer red sensor's window and solder with care two sensor's pin on PCB. Then connect sensor and check it's work. If sensor is working you can fix it on the part with nylon strip. Otherwise you can replace one by any 36kHz 3-pin IR receiver from TV remote control like TSOP1736. In car side connector: green wire is Ground, brown wire +5V, white wire Data.

TelmoChaparro

There is one on the Portuguese Mercedes Forum, if you want i can put it here...

iee

Hello my friend!

I know it's post from long time ago, but if you would be that kind and send to me a link for this post I would be very happy

Grree

Maybe this can help somebody.
Transparent compound could be removed using wooden toothpick and small heatgun (approx. 120° Celsius) be careful do not melt a plastic body. Refer to first picture how it looks without compound. Second picture shows crack around IR sensor pins, that's why sensor stopped working. Resolder pins and than use epoxy. After drying it will looks same as before.
Good luck!

XeRaTuL

that will help me XD

hand

I made a video of how to fix on 2004 mercedes c230.

Hope this helps get yours working once and for all !

VVF

Nicely edited video

What's the range, how far away can you be from the car?

Boom vang

great video, well done

Always thought that Siemens stood for quality, but seeing how our displays are fading and this circuit board has issues perhaps Siemens is the modern day Lucas

Moviela

Siemens is famous for cold joints on their circuit boards. It is not entirely their fault as the green nuts have passed RoHS in Europe and eliminated lead in the solder. I am all for limiting hazardous substances in the environment, especially where they can come in contact with children, but the removal of lead makes soldering difficult to master, and even properly executed joints are not as resistant to damage.

The sensor reacts within 1 or 2 meters from the key. The batteries in the key and the clarity of the window as well as the ambient Ir energy present affects the range. The distance is limited to allow you to see if anyone has an arm or their head through the window opening.

Mr. CVE

Thank you very much for the video.
It now works !!
Still have to point the remote at the sensor, but now can be a few feet away.

No standing at the front of the car and popping the boot

Small steps, I am happy !! .... for now !

C230 Sport Coup

Yeah, I love this feature. I've got both sides of the car working now.
Didn't know about the no lead thing in Europe.
Fixed my AC recently on a ford escort (backup vehicle inherited from my dad)
by fixing cold solder joints on a relay, so not just Europe.

Schweinhund

Dayumn son! GREAT VID! Thanks, my W210 E55 had this happen. Going for it. My vote for the best DIY Video Award!

Rubenc87

I actually have the video saved. Great job Hand.

Schweinhund

Well the W210 is different. The removal is about the same but there is no connector so I had to cut the wires. The sensor board is under a closed clamshell that has to be carefully pried off. The resin comes with it mostly. The sensor board itself looks much smaller and I couldn't identify the solder points. Plus they were really small. Anyway, I at least know how to replace it. Gotta get a new sensor now.

Milan Bojovic

I have W203 YEAR - 2002 - C220 CDI in Europe and I have followed your instructions from this page and from above video and it worked 100%

Thank you guys - great fix

slammer111

Big thanks for those who contributed to the thread. Especially to Hand for posting the video. Just had the driver's side fail, and fixed it for the price of a zip tie, a few drops of sealant, and a tiny dab of solder.

My 2 cents:

My understanding is that there are 5 potential failure points in the solder - 2 at the sensor end, and 3 at the connector end. A quick look under a magnifying glass revealed a cold joint on the sensor end for me. Thank goodness they used clear epoxy. I ended up resoldering the IR end (2 joints) only. I guess one can do all 5, but why fix it if it ain't broke right?

A heat gun can be used to remove the epoxy, but it isn't necessary. I simply used a tiny slot screwdriver (the ones used for glasses) and jammed it into the epoxy, tearing off chunks. The only part of the epoxy I removed was a tiny 5mm x 5mm square where the joints were located - just enough to uncover the 2 joints in question. I did scratch the PCB a little bit with the screwdriver towards the end (got impatient), but as long as the traces aren't damaged, it's fine. Even if a trace is cut, it can easily be joined with a dab of solder.

Don't worry if you accidentally melt part of the plastic housing. The only part that can be seen is the outer face of the hump anyways.

Instead of using a clear acrylic coating like in the video (I didn't have any and was too cheap to buy some), I simply used some silicone-based gasket maker to fill in the hole. Any sort of weatherproof caulking will do the trick. Although one can simply fill the entire gap, I decided to only use a thin layer, leaving an air bubble inside, and intentionally not letting the sealant touch the PCB or solder joints. That way if I ever had to do another repair in the future, the silicone can simply be peeled off to expose the PCB. Attached is the photo of the repaired unit. Notice that the black gasket maker is only on one end. 80% of the original epoxy is completely untouched.

A dab of silicone caulking is also great for "gluing" the sensor to the metal tumbler assembly too. A zip tie is still needed, but some caulking between the sensor and tumbler will eliminate any potential rattles, and can also be easily removed if needed.

C230 Sport Coup

Dude, you just got around to this? Sweet isn't it?
Comments.
You can just bend the metal tab and it will break off, it's pot metal.
No dremel needed,
And you can use the soldering iron to heat the clear substance that's in there and carefully dig it out with a toothpick.
Strongly recommend NOT using an exacto knive. Toothpick works great and won't damage the board or traces.

I tried to add some solder and ended up with too much and it was shorting a pin.
Things went south quickly. Removed all the solder with a solder sucker and then the solder I had wouldn't stick to the pins.
Ended up with a blob of solder, tried to dig it out and ended up damaging a trace on the board.
Waited several months to find another one on ebay for $40 (people wanted MUCH more and no best offer greedy basturds!)
and that time, I just heated the joints and cooled. Lesson learned.
Also I has some silicon sealer laying around so I just used that just like slammer.
It's been over a year now still working.

C230 Sport Coup

If anyone is interested, I have spare door sensors for both drivers and passenger door.
I'll be doing the 'fix', and testing on my vehicle.

If you don't feel comfortable soldering,
I can sell a repaired one, that's tested in a vehicle, with exchange,
for a fee of course.

relhoks

hump

C230 Sport Coup

Just pops off.

RafSabir

any ideas how to do this on a w204 need to take sensor out to solder but
dont know how it comes out

please help anyone

Chiro75

I attempted your fix and it worked the first time. When the temperature got hot, it stopped working. I attempted to resolder it but I believe my sensor is now toast or at least I can fix it. so....Yes I am interested in an IR sensor for my drivers door. My car is a 2004 C230K. If you still have some, Please contact me at TonyAChiro75gmail.com.. Thank you

RafSabir

I doubt u will need a new sensor - u probably havnt soldered it properly or put a short on it. I have done a few now - if u want to send it to me can have a look for u

Chiro75

Yes I would like to send the sensor to you and have you have a go at it. How do I contact you for mailing purposes? Chiro75