Mercedes R129 SL320 spare key

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You have the alarm switched off anyway, you said you turned it off with the key switch on the alarm siren so it’s permanently off.

Central locking won’t work while the immobiliser is disconnected.

The ignition should NOT be turned on while the cluster is disconnected from it's 2 connection plugs on the rear of the cluster, it causes the airbag warning light to stay on all the time.

Dec
 
Okay thanks, yes the alarm is off (sound bit) however I still had flashing indicators and central locking. Both are now off. Will keep you posted once transponder has been fixed


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This is just a Valet key, as far as I know will only open the doors and boot I think?

Not true, you can use it to start the car.

The car doesn't need keyless go either - that is reserved for later SL models so the chap your speaking to doesn't know what he's talking about.
 
The car doesn't need keyless go either - that is reserved for later SL models so the chap your speaking to doesn't know what he's talking about.

I think many alarm guys know the later cars well and assume the early ones are the same. We know better

The R129 has a lot of W124 in it. In the W124 the RCL (infra red key) central locking system comes in a number of versions: without immobiliser, with and with ATA. ATA is a separate thing and is the clue is usually a switch blank with a tiny LED in the centre

On top of all that there were a number of dealer-fit alarms. You can normally spot them by the alarm whooper (red or black) and a switch on a bracket half way up the LH side of the bonnet opening

It seems that the RCL keys are NLA and this will affect all Mercedes that used the RCL system. RCL has the detectors in the doors, single-button infra red keys and a brain under the rear set on a W124. I have not head of anyone being able to recode or rejig these systems but there's always a first time

RCL keys are coded to the brain and replacements could (till recently) be ordered by quoting the VIN

There's a further twist to this: RCL keys don't have the same numerical code as a standard key. So it's not possible to order a standard key for an RCL car as there is no key number. You have to cut them from an existing key - assuming you have one

The R129, particularly post-96 models, may have had features the W124 didn't. AFAIK no W124 had a transponder key

As usual with these cars there are no hard & fast rules

Nick Froome
 
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I think many alarm guys know the later cars well and assume the early ones are the same. We know better

The R129 has a lot of W124 in it. In the W124 the RCL (infra red key) central locking system comes in a number of versions: without immobiliser, with and with ATA. ATA is a separate thing and is the clue is usually a switch blank with a tiny LED in the centre

On top of all that there were a number of dealer-fit alarms. You can normally spot them by the alarm whooper (red or black) and a switch on a bracket half way up the LH side of the bonnet opening

It seems that the RCL keys are NLA and this will affect all Mercedes that used the RCL system. RCL has the detectors in the doors, single-button infra red keys and a brain under the rear set on a W124. I have not head of anyone being able to recode or rejig these systems but there's always a first time

RCL keys are coded to the brain and replacements could (till recently) be ordered by quoting the VIN

There's a further twist to this: RCL keys don't have the same numerical code as a standard key. So it's not possible to order a standard key for an RCL car as there is no key number. You have to cut them from an existing key - assuming you have one

The R129, particularly post-96 models, may have had features the W124 didn't. AFAIK no W124 had a transponder key

As usual with these cars there are no hard & fast rules

Nick Froome



Hi Nick, thank you for your detailed response. The info around 'keyless Go' comes from the after sales manager at Watford Mercedes who says I cannot order a credit car type key for my SL320 because of the lack of 'keyless go' system. I simply don't know what that means?. What I have established from here is my vehicle has a Scorpion alarm system with a transponder in the key. My transponder was lost after the key was broken by a hotel valet. I do have a spare but I am concerned if I lose this then that's game over. So With no choice left I am sending the immobiliser and the broken key to a an expert in Lesta to reprogram a new transponder for my key.


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Hi all,

Mark here from Replacementmercedeskeys.co.uk

Just to clear up anything written about whats been said by me or my staff..

Firstly, I CAN make a key for the r129...

Be it a transponder emergency key or a remote (Depending on what system it has and if we have the correct remote in stock) we can make a transponder from a DAS (RFL/ATA) box without a problem..

Please be careful who you take your RFL box to, the MCU inside (Which as it happens has the same name as my user name - HC705x32) can be easily damaged when removed and erased upon reading if care is not taken. I have seen many RFL box's from SLK, old W202's and many others when so called specialists have removed the chip and made a mess of the box and deleted the data making it impossible to use again.. try ordering a RFL box if you can't even get a key!!

If you ring me, I will always ask for the car to be at our workshop as the procedure could take a bit of time and it is very stressful trying to do everything with a customer waiting for an unknown time.. We can produce a transponder only key within 20 minutes - BUT its the Remote side of the job I cannot be sure on, as no one has ever done it before...

I also make full w163 remote keys, 1 button keys for the W202 - but not the SLK key yet as the learning procedure for the remote is unknown so I can only make a transponder blade key for that..

Keys that can be made by me - Bladed remote keys.
R129 SL
W163 ML 3 button
W202 C Class
W210 E Class

If a remote cannot be made, at least we can make a blade key with a transponder which will start the vehicle (we can also set it to turn off the alarm with the transponder)

We have made keys for main dealers around the country (a fair few) for w163 ML's and R129's so the main dealers know about us already..as do MB uk..

Feel free to ask any questions - and sorry mods if this post is not allowed..

[email protected]
 
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Hi Mark, thanks for your detailed response. Unfortunately when I rung you guys the response I received was not very positive given the first thing I was told was to go to Mercedes to buy from them. Having explained the issue a couple of times the advise was to bring the whole car to Birmingham and drop it off for a couple of weeks but again there were no guarantees. I got details of a couple of businesses in Lesta and Ireland from this forum who said they could do the job without the car and only needed the immobiliser and any spare key I had.

For all who are watching this thread -Autotronics in Lesta have completed my job with a bonus 3rd key with transponder. So I have 3 working keys and am well pleased.
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All works well, thank you all for your advice and support. Hopefully this thread will help other R129 owners.


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Folks - I put everything back together today and everything works fine. So I have two keys with remote central locking and one spare with transponder. All sorted!
For those who wanted to know the location of the immobiliser, I have attached some close up images.
99f12f322fef8a0deb35328a8c697d62.jpg
e1755b76fcb4d411ff6f48a70478411b.jpg
54c11d445b2c60f62f6d86ec9519bda6.jpg



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Apparently the keys are now available again...guess there were enough requests to have a new batch made.
 
I have just found this thread, it is very interesting.......
 
They are out of production again and have been for some months.
 

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