wizkid

I have searched this forum over and I can't find anyone that has posted a solid fix that they have done themselves when your remote stops working from a distance.

2002 C240 Sedan

One day, the car suddenly stops receiving inputs from both my keys unless I point it at the IR receiver on the door handle one inch away. Great, so I change the batteries in both. Still, I have to be one inch from the door handle to lock or unlock and that is iffy at best.

I purchase a new key with skeleton. $200 with tax. Ouch!

Same problem, except I can be two inches away from the door handle.

I am assuming this to be a radio receiver problem in the headliner. Has anyone fixed this themselves? If so, how and what parts.

I will do a DIY on this to post on my site but I need help to get that far.

Other notes: Radio reception seems fine. Windows are tinted.

TIA!

SeaCoupe

WHAT?! You come in here and don't give us a mileage update!

The nerve of you!

178K

E

paypaboi

Same boat....free bump...because I am curious too...

TemjinX2

happens to me too sometimes, but only when it rains..which is strange.

On a side note, i'd like to thank for your website wizkid. Its helped me a lot, looking your maintence diy's.

tommy320

Bump for this thread, does anyone have a clear answer to this problem?

bdgdl08

Install University FTW! This happened in the CLK once, but I have no clue.

BigBodyBenzC240

I have heard of people changing the small black infrared reciever on the driver and passenger door handles which made the lock/unlock like brand new. The tint is also a factor as it has already been discussed somewhere on here and tells you where tint needs to be removed. GL with the fix!!!

Glyn M Ruck

- No metallic tints
- Check wires not cut from rear screen when applying tint.
- Check stick on connector under center rear roof lining
- Check antenna amp earth in rear C panel
- Check antenna amp is not blown

Do a nice DIY for us.

Good luck

Here is a comment I posted earlier

"Yes the Aerial is built into the glass. The Amplifier is mounted above the rear screen on Coupes & in the LHS C pillar in sedans.

If tinting has been done then water frequently shorts the antenna & blows the RF amplifier or when trimming the tint they cut through the wires/traces as they exit the glass.

Metallised mylar tints frequently ruin radio & remote reception. Radio & remote share the antenna/aerial - Only option - remove & replace the tint.

So we have 3 potential problems.

- The tint itself
- Bad amp earth
- A blown RF amplifier
- A damaged antenna trace in the glass or wiring above the glass

The worse case scenario requires replacement of the rear window. The amplifier replacement is relatively easy."

kcheng86

I have the same problem..cant find out whats wrong.

Glyn M Ruck

What have you checked? All of the above are relatively easy to check. Hopefully wizkid will do a step by step for those that don't feel confident. BTW you don't have to remove the roof lining & the back C pillar cover is easy to remove/

Install University rocks

tommy320

Glyn, Thanks for the post. This weekend I'll begin inspection of the earth (ground as I know it in the states) and the fuse. Does anyone know the part number for the amplifier and approximate cost?

Thanks!

Glyn M Ruck

These have been the amplifier numbers for the 320 - suggest you check which one you have.

010 2038206489 001 AMPLIFIER ANTENNA
010 2038206689 001 AMPLIFIER ANTENNA
010 2038209889 001 AMPLIFIER ANTENNA
010 2038270742 001 AMPLIFIER ANTENNA
010 2038271942 001 AMPLIFIER ANTENNA
010 2038200989 001 AMPLIFIER ANTENNA
010 2038206889 001 AMPLIFIER ANTENNA
010 2038206989 001 AMPLIFIER ANTENNA
010 2038207289 001 AMPLIFIER ANTENNA

Good luck

chocobear1

Same problem with the wife's 2004 C230K Sport Coupe, 79,000 miles and way out of warranty. AM/FM/IR no workey. Took it in for cam sensor warranty work and asked SA to diagnose this issue. He came back with a quote of $1093 parts and labor. LOL!! Seems this is about average since I called a couple of other MB stealerships in the Houston area. One even quoted me $1100 for the part and $800 for labor. OUCH!! Needless to say, I did not get this fixed. I was also told by a mechanic friend that some electronic components on MB's need to be "activated" properly and can only be done by MB techs themselves or you run the risk of further damage. Can you shed some light on this Glyn?

Glyn M Ruck

Yes - certain Benz components need to be "adapted" & recognised with a Star DAS. The antenna amp is not one of them. I hope you meant to say the AM/FM/RF or is your IR down as well? Do you have to use a hard key to lock & unlock the vehicle?

chocobear1

Sometimes we do have to use the manual key to unlock the car followed by a scurrying into the car to turn off the alarm. The SA told me it was the "comm bar" or communications bar. Nevertheless, I'm gonna have to find an alternative. Maybe DYI the fix if you think the headliner isn't that tough to remove/replace.

PiratePast40

I have the problem with only one of my key fobs. I'm assuming that it's the RF portion of that unit and not the receiver end of the system since the other one works. For the other people, it would seem unlikely that both keys RF failed but would be nice to be able to verify if it's the transmitter or the receiver system that has failed.

Glyn M Ruck

You don't have to remove the headliner. You can access the sticky connector at the center rear of the screen in the gap. Take a look with a dentists mirror. The C panel cover comes off with the removal of one screw if I remember correctly to expose the antenna amp which is usually what fails on the RF side.

Glyn M Ruck

If only one key does not work the problem lies with the key.

Phin

OP...I had this problem when I had my 05' 230...Service Advisor said it was a FM "receiver" software upgrade...IIRC...my car was under factory warranty at the time though...GL

Glyn M Ruck

That's the first time I've heard this one - I did not know there was any software/firmware to update - did you have Command?

Phin

...no I didn't have command....also this is what the SA had told me...so I can't say that was the cause/cure for sure...but I can't see why he wouldn't tell what was what...

HellsAngel

same problem for me, sometimes it works when im 2" away, somtimes it dont... i am currently using the hard key... i dont have a tint... i think its the amplifier antenna but i'll keep you updated

Glyn M Ruck

If you have no tint then 90% of the time it's that sticky pad connector - you can just push on the headlining or a blown amp. I think Benz have had crap with these amps - I can't believe the number of different part numbers for the same vehicles.

tommy320

I know this may not fix everyone's situation reading this thread, but it did for me.

I was getting the no reception from far, and limited results from within 2 inches with the IR. I tried changing batteries at first, but that did not fix the problem. I then tried to use my spare key from a distance and it did not work either.

So I assumed that i must have a bad amp or receiver since neither key was working. This morning I began to check all the fuses (all good) and the ground (good as well) to try and track down the problem.

On a fluke I decided to use my spare key, since I have never used it since I got the car. I put the key in the ignition, turned on the power to make sure the car was recognizing the key till I saw the SRS light come on, and listed to a little bit of music as I contemplated how much this was going to cost to fix (maybe about 20 seconds).

After removing the spare key from the ignition I tried again to use the key fob and like magic it all worked, both keys, from at least 50 feet away. I don't know the technical reasons why this worked. My best guess is that the car needed to recognize both keys after I replaced the batteries in order for it to allow the remotes to work properly.

Recap: If you have replaced your batteries and are now not getting any reception go take both keys and place them into the ignition and turn to when you see the SRS light come on.

I may have just gotten lucky, but i didn't know this and it hasn't yet been addressed in this thread at least.

Good luck.

Special thanks to Glyn for all the information as I tried to track down this problem.

HellsAngel

The car knows if you have 1 or 2 or more keys ?
I cant try this because i have only one key...