HELP: Key Problems

Jul 28, 2010 | 02:37 PM

benzpride

Thread Starter

Junior Member

Joined: Jan 2007

Posts: 16

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From: Mission Viejo, CA

C240

HELP: Key Problems

Hey guys,

If someone could direct me on where to go/what to do.

So i got my c240 key wet and after had some problems with it, but it finally was recognized by the ignition BUT in order for me to open the car I have to put the end of the key next to the infrared on the car.

Is there any way I can fix it again, so I can open the car without having to be next to the infrared sensor?

Jul 28, 2010 | 02:45 PM

LILBENZ230

MBWorld Fanatic!

Joined: Jul 2008

Posts: 8,384

Likes: 800

2019 G70 6MT & 2022 Ford Maverick XL

Water is not the key's friend. You will probably have to replace it.

Jul 28, 2010 | 03:04 PM

govertime

Member

Joined: Apr 2006

Posts: 167

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you could try changing the battery and/or taking the case apart and cleaning the circuit board with alcohol and lint free cloth. its probably worth a shot at the price these sell for.

Jul 28, 2010 | 03:14 PM

MW_ATL

Super Member

Joined: May 2009

Posts: 818

Likes: 3

From: Atlanta, GA

'02 C230 Coupe (Me) '03 SLK320 6MT (Wife)

Hmmmm. The infrared sensor should be for the convienece feature (opening closing the sunroof and the windows) and a radio signal should be used for the locking/unlocking, etc.

That is why some people with metallic tint have problems with the unlocking. I believe the antenna is near the upper part of the back window.

That sounds a lot more like the battery got drained on your key. Not sure why, but if I were you, I would try pulling the battery and all out of your key, letting it dry very well and trying a new battery.

Jul 28, 2010 | 07:13 PM

Glyn M Ruck

Super Moderator

Joined: Jun 2008

Posts: 19,942

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From: Llandudno, Cape Town, South Africa

late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires

Read the many threads on RF failure/metallic tints. The RF side of the key is down. Wash out key with hot alcohol, give it a dry with a hair dryer (not too hot!) Put in new batteries. Does your spare key work normally? If so & you can't revive the troublesome one you are in for a new key. If they both don't work the whole rear window antenna, sticky contacts & antenna amplifier are suspect. The EIS inductively powers the key once in the ignition. Batteries play no part at this point.

Jul 28, 2010 | 10:54 PM

benzpride

Thread Starter

Junior Member

Joined: Jan 2007

Posts: 16

Likes: 0

From: Mission Viejo, CA

C240

I did dry the key and took it apart after I get it wet from water and was able to get it working. Problem is I had to take the battery unit and put it into my spare key (as the spare key battery was out). So now I am using the spare, which has the same body as the regular c240 key.

So hot alcohol and new battery? Battery seems to flash even when I am far from the car....

I'll read up on this, but I don't want to destroy the spare key, so I'll give it a shot on the original key that was damaged and see what happens.

Anyone who had a similar experience, chime in!