Frightened new owner: W124 Key identification and help with remote central locking

[roastbeef]

Has the tail gate lock not got a key hole thought they all had ,could you not lock the car manually from there not ideal I know but at least the car would be locked

 

[ashimashi]

Has the tail gate lock not got a key hole thought they all had ,could you not lock the car manually from there not ideal I know but at least the car would be locked

It does but it doesn't activate the central locking, only locks and unlocks the tail gate.

I think at some stage someone disconnected alarm/immobiliser and banjaxed the whole thing?

 

[Dec]

There is also the possibility that the car had its own alarm remote like the one in the centre of picture below and this remote is now missing or broken and so you weren’t told about this remote when you bought the car.

Any chance of contacting the last owner, not a dealer, if it was bought from a dealer.

Just test the remote again, through a digital camera, you should see a Red flash and then a Blue/White light while you press the button.

Dec

[YOUTUBE]zQhwvjw29NA[/YOUTUBE]

 

[kingdave]

My 124 estate behaved in a kind of similar way when I got it. The only difference was that I could unlock all the doors and tailgate using the passenger key hole.

My plipper passed the camera test (you could see an IR beam on a digital camera), but still didn't work.

My local MB specialist resoldered the switch inside the key and after that it did work.

So - I conclude that you may have more than one problem. If the plipper was working but you just had a vacuum fault I would expect that the tailgate or driver's door red and green LEDS would light up when you try and operate the locks. I can't stress enough you need to be close to the locks and literally shining the IR beam at the keyhole IR receiver on the car.

Your passenger door lock should operate the central locking so regardless of the state of the plipper you've got another problem there.

 

[ashimashi]

Just test the remote again, through a digital camera, you should see a Red flash and then a Blue/White light while you press the button.

Yep, I get the blue light through camera.

Yep, passenger key isn't working as it should (locking all doors) probably it's caused by removal of the alarm.

 

[Dec]

If you have them in your car, the old ceramic fuse can be a problem and should be cleaned to make sure that the are making good contact, there may be a separate fuse for the infrared locking receiver.

https://mercedessource.com/problems/electrical/oe-aluminum-fuse-failure

Dec

 

[ashimashi]

Result! Got the fob working, thanks a mill for all your help Grober.
For future reference, after a few futile attempts at reprogramming, finally the instructions provided at the end of this post (as highlighted by grober) sorted it out:
http://www.mbclub.co.uk/forums/375628-post23.html
The car is a 1995 W124 E220

I am not going to buy a used fob from the states (something like this: Mercedes 1407601406 Factory OEM KEY FOB Keyless Entry Remote Alarm Replace | eBay and have it programmed the same way - it's the same part number) and a new casing/blade (something like this:1 Button Flip Key Shell Fob CASE Replacement For Mercedes Benz W168 W124 W202 | eBay and have it cut) and frankenstein another fob - this should work, or am I missing something?

 

[Dec]

The general opinion is that a remote like yours from another car can’t be programmed to work on your car, regardless of what the seller says.
I’m on this site for nearly 10 years and have never heard of it being done.

Dec

 

[ashimashi]

The general opinion is that a remote like yours from another car can’t be programmed to work on your car, regardless of what the seller says.
I’m on this site for nearly 10 years and have never heard of it being done.

Dec

Dammit - thought I could reprogram any used one the same way as this one.

So the only option would be 220 quids to the Irish Stealerships! I wouldn't feel comfortable with only one key and fob!

 

[bolide]

There is a mass of misinformation is this thread. A few points:

* There is no sensor on the interior mirror on the W124 so pointless pointing the key at it
* the tailgate has a keyhole and a remote sensor
* the tailgate lock should activate the central locking
* the passenger lock should activate the central locking
* the key is part of a factory-fitted system (RCL)
* the keys are not reprogrammable (ie you can't buy another key & reprogram it)
* new keys are around £190 each
* keys are ordered using the VIN
* the key code is tied to the brain via the VIN & MB records
* the brain isn't coded to the car so you can swop key/brain sets between cars
* RCL comes with or without a factory alarm
* some RCL cars have an aftermarket alarm
* removing an alarm should not stop the central locking working

Nick Froome

 

[Dec]

Dammit - thought I could reprogram any used one the same way as this one.

So the only option would be 220 quids to the Irish Stealerships! I wouldn't feel comfortable with only one key and fob!

You could wait until you lose it, and then order a new one from the cars VIN number, it might never happen, but if it does, it could be inconvenient as it could take up to a week to get a replacement.

Is you feeling lucky?

Dec

 

[ashimashi]

* the tailgate lock should activate the central locking
* the passenger lock should activate the central locking
* the key is part of a factory-fitted system (RCL)
* RCL comes with or without a factory alarm
* some RCL cars have an aftermarket alarm
* removing an alarm should not stop the central locking working

Nick Froome

Brilliant info Nick, thanks.
What confuses me is this: how is it that the fob works and locks all the doors now when pressed, but turning the key in passenger door or tailgate doesn't? It's quite baffling!

Also, how can I find out if there is a factory or aftermarket alarm or immobiliser? Can it be gleaned from the VIN or would the dealer know?

Thanks again for the precise and accurate info.
Ash

 

[ashimashi]

You could wait until you lose it, and then order a new one from the cars VIN number, it might never happen, but if it does, it could be inconvenient as it could take up to a week to get a replacement.

Is you feeling lucky?

Dec

I think I'll wait an make sure everything else is ok with the car and it's a keeper before ordering another key from the dealer!!

 

[bolide]

The dealer won't have a clue re alarms. if the car has a blank switch with a tidy red LED then it has ATA (Anti Theft System) which does have an immobiliser. It's a rare system. I've seen RCL systems with alarms and without, ones with alarm sounders and some without

If it has a red alarm siren on a bracket on the inner wing and a switch half way along the bonnet edge on the offside that's a dealer or factory system. Anything made by Scorpion may be a dealer-fit aftermarket system

The best thing to do with any aftermarket system is to rip it out

Unplugging the locking pump will do nothing - it's a pump, not a brain

If some of the door locks don't work the locking there's a fault. Each lock has a pneumatic actuator to lock & unlock. We know that works so the signal from the lock to activate the locking must be at fault on the tailgate & passenger door

Check to make sure the tailgate locks when you lock the car - in one (key) lock position it doesn't follow the c/locking so may be unlocked when you think it is locked…

Nick Froome

 

[grober]

There might be a misconnection or bad connection at the pump---- has been known especially if the pump has been replaced at some point. Check under the rear seat [ drivers side in RHD models ] to make sure the pump connections are fine and that there's no water ingress

I am slightly puzzled because at the start you said that the car did unlock with the key in the passenger door- maybe I misunderstood?? ReSync-ing the key should not have affected this . Are you sure you are turning the key fully in the lock in the right direction- locks will be possibly be quite worn by this time making their operation a bit flaky?

 

[ashimashi]

Nick and Grober,

Thanks very much for your advice. Unfortunately I haven't got around to do a proper inspection yet, it's so dark these days, and by the time I get home it's already pitch dark -and rainy!

I took a quick photo of something that looks suspiciously like an aftermarket alarm led on the dash, maybe that'll make things clear.

What you say about the connectors to the pump makes perfect sense, I will give it a go as soon as I can.

So Nick, if I go to an alarm specialist they should be able to get rid of the aftermarket alarm without affecting the RCL, right? I don't care about alarm or immobiliser, I just want to be able to safely lock/unlock the car without the risk of being locked out or stranded.

 

[bolide]

That's aftermarket. It should be obvious to an installer what is aftermarket and what isn't

One clue is that later aftermarket alarms have wires all the same colour whereas the MB wiring is all colour coded

Nick Froome

 

[Druk]

As an aside and as per your pic, you need to clear the dead leaves from the rear water channels. 124's in particular have a habit of choking up the drain channels at either end behind the battery/servo and the water then floods into the car via the heater.
You'll find two little drop holes at either end behind the bonnet hinges. Rod them through with a curtain wire or similar.