1994 280SL immobiliser help bypass and fix

[swast4]

Hi,
I am trying to get my Mums 1994 280SL back on the road again but the immobiliser is becoming a problem.

She has had the car for 6 years now and occassionally the immobiliser hasn't switched itself off, when I have come to it I have usually got it going again by cleaning the fuse in the boot by the hinge, it usually gets corroded. But last week it has let her down twice in a week leaving her stranded. She is borrowing my car at the moment because she is loosing confidence with hers.

I would like to remove the immobiliser or bypass it as it is becoming more hassle than it's worth on her 13 year old car. I know it is located in the near side footwell but am unsure of what is required to bypass it. Please could someone e mail me away from this forum with the solution. adam.stapledon@shell.com

Thanks..............Adam

P.S. When the AA man came to help her last week I was hoping that they would do this but didn't all they could do was check fuses and disconnect battery, which didn't do anything. It was only when she tried it later after about an hour that it worked.

P.S. It's not the battery in the remote as the remote still operates on the passenger door and boot lid fine, and it doesn't have the detector on the rear view mirror.

 

[brandwooddixon]

I take it that you've changed the batteries in the key fob. It's quite possible for the key to unlock the car, but not start it.

Television may be able to give more advice, but it may be the reader in the ignition key barrel.

 

[bigasotonuk]

Hi,
The alarm that is fitted to this car 'should' be a Scorpion which was fitted by the importer or dealer from new.
Brandwooddixon is quite right the fob will still operate the locking but not the immobiliser if the batteries are even slightly flat i have to replace mine every 3-5 months to keep the alarm working correctly. You can bypass the immobiliser, but i would seriously advise against this as SLs, i would consider are still a target for joyriders, and as insurance goes you may find that the price they give for the cover takes into account the Mercedes Alarm System my insurance company certainly does.
I,ve e-mailed you a link of a site where there is information on Scorpion Alarms, this should give you the info you require.
To identify your alarm 'apparently' there is 3 figure number on the alarm siren.
The immobiliser is bypassed via the alarm control box, then shorting out two cables that go to this unit.
Hope this helps, post back and let us know how you get on.

 

[swast4]

Thanks for your help and advice, I found out when looking through the service history that the alarm and immobiliser was fitted in 1998 by Mercedes, I located it and got an auto electrician in. He has taken out the immobiliser and cost me £30, I thought job done !! but it is still playing up but I think it is the control unit as the boot it is very temperamental in swiching the alarm of ie going to green on the door handles or boot lid. We have changed the batterys in the remote but it is still doing it. I think it is the control unit for the locks, does anybody know where it is located ?
Thanks,................Adam

 

[bigasotonuk]

Hi,
From the previous posts i,ve read regarding alarms of this era most control units appear to be mounted in the passenger side footwell/behind dash.
Though 1 members w202 it was mounted in behind the drivers side of the dash.
Identifiying maybe a problem as it will not have 'Scorpion' written on it just a Mercedes pt. no.
Hope this is of some help.

 

[claropark123]

I've got a similar problem with a 1994 e300 estate, just changed the battery, old one was flat, and all hell broke loose. Didn't realized the immobilizer and alarm still worked, but clearly they both do.
Have changed the 'flicker' battery with a brand new one to no avail.
Can anyone help?

 

[muller1996]

Hi,
The alarm that is fitted to this car 'should' be a Scorpion which was fitted by the importer or dealer from new.
Brandwooddixon is quite right the fob will still operate the locking but not the immobiliser if the batteries are even slightly flat i have to replace mine every 3-5 months to keep the alarm working correctly. You can bypass the immobiliser, but i would seriously advise against this as SLs, i would consider are still a target for joyriders, and as insurance goes you may find that the price they give for the cover takes into account the Mercedes Alarm System my insurance company certainly does.
I,ve e-mailed you a link of a site where there is information on Scorpion Alarms, this should give you the info you require.
To identify your alarm 'apparently' there is 3 figure number on the alarm siren.
The immobiliser is bypassed via the alarm control box, then shorting out two cables that go to this unit.
Hope this helps, post back and let us know how you get on.

hello, Hopefully you can help and are still on this forum, I have a 1996 C180 that i left idle for over 1 year. The battery died, now when trying to start the mirror lifts red/green flash alternatively. The key fob opens all the doors etc but will not start the car. Can you help me disable the immobilizer?