W210 e300 td key fob issue

candyman1980

Member
Joined
Jan 24, 2009
Messages
23
Reaction score
0
Location
Portsmouth
Your Mercedes
E300 TD
Morning all,

I've had a starting problem recently which required me to remove the battery to re-charge over night. I put the battery back in this morning and locked and unlocked the car without a problem. However, when I put the key in the ignition no lights came on on the dash and I wasn't able to turn the key to position 1.

I connected the battery up to another car (which was running) just to make sure that it wasn't a case of a dead battery and it didn'timprove things...

Is there any way of establishing whether the key is knackered or the ignition itself? I'm assuming it's the key....I do recall throwing the keys (maybe against a wall!) yesterday when it wouldn't start and perhaps I've broken something. I phoned MB this morning and they want £250 for a new fob!!

Any help would be most appreciated!
Cheers
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
331
Age
86
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
You will have broken of the transponder pick up coil within the key, they can sometimes be soldered back on, but not always
 

Attachments

  • Picture 608.jpg
    Picture 608.jpg
    43.7 KB · Views: 43
OP
C

candyman1980

Member
Joined
Jan 24, 2009
Messages
23
Reaction score
0
Location
Portsmouth
Your Mercedes
E300 TD
  • Thread Starter
  • Thread starter
  • #3
Thanks for the reply....

When you say transponder key - is that not referring to the RF section of the key fob that controls the remote locking? That works ok.
I was of the understanding that the ignition circuit was an inductive IR one and wasn't related to the RF stuff...correct me if I'm wrong!
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
331
Age
86
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
The key has 2 parts the locking and the starting, and they have no connection at all. the locking takes place using the internal batteries, when in the ignition lock it uses the transponder coil around the lock to energize the coil within the key to provide the voltage to energize that circuit
 
OP
C

candyman1980

Member
Joined
Jan 24, 2009
Messages
23
Reaction score
0
Location
Portsmouth
Your Mercedes
E300 TD
  • Thread Starter
  • Thread starter
  • #5
Ah sweet...perhaps I can save myself £250 after all! thanks again
 
OP
C

candyman1980

Member
Joined
Jan 24, 2009
Messages
23
Reaction score
0
Location
Portsmouth
Your Mercedes
E300 TD
  • Thread Starter
  • Thread starter
  • #6
I've opened my key fob up and found a couple of damaged components. Now I'm not sure what they are as there's not any meaningful markings on them. It's a different circuit board to the attachment in the earlier post but I'm still hoping to salvage it. It's a 3 button one - lock, unlock and boot open.

I'm planning to get another fob off ebay and just swap those 2 components. Now I know there may be an issue with the component that stores the security information - I'm assuming that that info is held in the eprom chip...does anybody know if that's right?

Thanks
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
331
Age
86
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
There are three versions of the key, on the last versions the coil was modified so that it could not fall off if the key was dropped, there will not be anything wrong with the IC's
 
OP
C

candyman1980

Member
Joined
Jan 24, 2009
Messages
23
Reaction score
0
Location
Portsmouth
Your Mercedes
E300 TD
  • Thread Starter
  • Thread starter
  • #8
Thanks Malcolm.... I have attached a photo of the damage.

You can see in the centre of the photo the damaged component. Not sure what it is.. looks like a crystal perhaps? You can see the lid fell off and is next to the PCB. The lid has 167 printed on it - is this a generic marking or is this part of the security check circuit?

Quite worryingly, the IC on the other side of the board is marked 267 which leads me to think they're related and that replacing one won't do the trick....

Any ideas if/where I can get a replacement for the broken component??
 

Attachments

  • 08072009275.jpg
    08072009275.jpg
    486.7 KB · Views: 74

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
331
Age
86
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
Well I have repaired at least 25 keys but I have never seen one like that, the broken part is a Xtal I think and not an IC
 
OP
C

candyman1980

Member
Joined
Jan 24, 2009
Messages
23
Reaction score
0
Location
Portsmouth
Your Mercedes
E300 TD
  • Thread Starter
  • Thread starter
  • #10
Ah that's disappointing! There must be a crystal on the other types of key fobs - is there any chance you can post any markings that appear on the crystal on the other types please? It may be the same but may be specific to the car :(
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
331
Age
86
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
I already checked my spare keys but nothing the same on them.

I have been all through the RS book,but nothing in that package with 4 legs, so if not a Xtal could be a photo iso coupler, its odd that on your key its all on one side, and the transponder coil is on the front.

I have sent the picture to a friend to see if he knows.

A google search showed nothing in the first 30 pages, a prefex may help
 
OP
C

candyman1980

Member
Joined
Jan 24, 2009
Messages
23
Reaction score
0
Location
Portsmouth
Your Mercedes
E300 TD
  • Thread Starter
  • Thread starter
  • #12
Yeah I know there isn't much to go on unfortunately. We checked it out under an inspection microscope and certainly looks like some kind of xtal and it has a crack running through it so I'm assuming it's shot!

It would be great to see if your friend has any ideas on the subject....this is looking more and more like I'm going to have to shell out £250 for a new key - and all for a key that doesn't start!!
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
331
Age
86
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
You still have the Ebay option as long as there is a photo the key in question
 
OP
C

candyman1980

Member
Joined
Jan 24, 2009
Messages
23
Reaction score
0
Location
Portsmouth
Your Mercedes
E300 TD
  • Thread Starter
  • Thread starter
  • #14
...update....finally got an old key fob off eBay for £12.00, swapped the 2 damaged components and hey presto - the baby started and more importantly I saved £250!!
 

television

Always remembered RIP
Joined
Mar 14, 2005
Messages
164,073
Reaction score
331
Age
86
Location
Daventry
Your Mercedes
2002 SL500, 216 CL500, all fully loaded
...update....finally got an old key fob off eBay for £12.00, swapped the 2 damaged components and hey presto - the baby started and more importantly I saved £250!!

Great new candyman,,its rewarding isnt it
 
OP
C

candyman1980

Member
Joined
Jan 24, 2009
Messages
23
Reaction score
0
Location
Portsmouth
Your Mercedes
E300 TD
  • Thread Starter
  • Thread starter
  • #16
Yep it is....although I've had to drive a D reg nissan micra round while waiting for the key! Saying that, the micra cost me the same as a new key and had tax and mot and does 60mpg on the motorway to boot! Seems to be more reliable too....nothing electric to go wrong!

Thanks for everyone's input, much appreciated, this site's a great resource... I wish I'd stumbled across it before buying the merc!
 

Stop looking for the Best Garage!! We are here and have the best advanced solutions for you, at Competitive prices. Put us to test with any issue you may have.
Top Bottom