Just wanted to confirm that i used the car extensively today, no alarm and no problem starting...finally i could stop unlocking my car from the trunk :thumbsup:

 

So, I've had much the same issue with my '92 300D (drivers side door and alarm going off) A++ for timeliness on this topic. As I was heading home from work today my alarm started going off while I was driving (flashing lights, horn, etc). Gives new meaning to drive it like you stole it I suppose. I pulled the carpet and plate up and unplugged what looked somewhat similar to the post on the ’93 (but then a little different too). I’m hoping someone will confirm I did it correctly.

Did this 30 minutes ago, and did a quick function check. Couldn’t find anything that wouldn’t work after I disconnected the two harnesses and no airbag deployment (my fear). I'm hoping I can go down town tomorrow and not draw attention to myself..

Guess I could have removed to gum wrapper, but hopfully this picture will post.

 

Yes, those are the correct plugs....you are lucky you did not have to pull the cluster like me :thumbsup:

 

If the alarm goes off when you unlock the driver's door, the fault is most likely the electrical switch attached to the lock tumbler assembly. You can buy the switch separately from the lock tumbler assembly.

I agree though, the factory alarm is more of a nuisance than a theft deterrent. A serious car thief won't be slowed down by any alarm, either factory or aftermarket. The best prevention is to not park your car anywhere that it might get stolen!

:thumbsup:

 

Car swings but dont start

I was dumb enough to jumpstart my 1989 w124 230e. Now my ignition lights does not go on when I try to start the car. Nor does the car start. It swigns though. After connecting a line from battery to coil the car started. I was told that it is my immobilizer. Any advice.

 

I was dumb enough to jumpstart my 1989 w124 230e. Now my ignition lights does not go on when I try to start the car. Nor does the car start. It swigns though. After connecting a line from battery to coil the car started. I was told that it is my immobilizer. Any advice.

Check the fuse on your OVP relay... you might have fried that relay during the jump start...

if that is ok, you could bypass your k38 relay to disable the immobilizer similar to the manner described in this thread...

good luck :thumbsup:

 

These older post are always helpful. Thanks to all who provided information on disabling the alarm system.

 

Immobilizer



I agree the post is as relevant today (and I do mean TODAY) as it was when posted.

In my case the immobilizer appears to randomly engage and disengage. In other words, intermittent no start conditions, and no rhyme or reason for when the alarm will sound (that I can figure out). And twice the car stalled or failed to start while I was in the middle of the street. Such stress.

 

Thanks latief my 89 300te has the same problem, which killed the brand new battery that I lust dropped in it made me so mad. Thank you man.

 

HELP

I was driving my car and suddenly the alarm and the immobilizer went on. I went out of the car and locked it, and unlocked it again. Then the alarm stopped and when i opend the door, the alam started again. What should i do?
B.T.W. it`s a MB W 124 300TD 94 model

 

What should i do?

Start a new thread on the forum. This thread is about how to disable the alarm, not repair a cranky one...

:thumbsup:

 

oki

 

i ripped apart my inst cluster and this relay was not avail... also my cover on the floor was a bit different... no idea where this relay may be.. looked all over no wires of that color even ....:surrender:

 

Found K38 relay on '95 S320



I located K38 relay hidden in the back of the main fuse box. I had given up on looking for relay and was just going to run wires to starter/solenoid when I found relay in rear of fuse box. I had no luck jumping the wires on the relay, starter still doesn't crank. I ran wires to a push switch to activate starter. I did this after discovering I could start car with screwdriver by touching the hot lead on starter and the smaller lead on solenoid.

 

Bystov, yours seems to be an 87. You will not have the really.

 

so how do i remove this alarm ? im tired and so are my neighbors and its a matter of time till i get my windows smashed or a good spash of 5F5 on my hood. i live in the ghetto and keeping car open all night is not an option

 

read step 3.



Step 3: Unplug those big plugs. On pre 1993 cars, this should be sufficient to disable the car. Not the case though for 1993+ cars as they have an immobilizer feature that is triggered when the alarm is disabled. so my car would not start after unplugging those two plugs.

 

going to go try it now! thanks mate

 

Excellent write up of disarming alarm system. I just can't find the K38 relay. I pulled instrument cluster on a '95 S320 looking for K38 relay. My car also doesn't have the speedometer cable either. Can anyone help me find the K38 relay on this car?

 

dont think its the same set up on a w140

 

I've learned a trick that seems to stop my alarm from going off when unlocking from the trunk. It looks as though the door locks become slower to unlock as the weather gets colder. I've discovered that if I open the trunk before all the locks are up, the alarm goes off. If I wait for all the locks to come up, no alarm. When it's after dusk, I can usually look at the alarm light on the center console, but if it's bright out, I watch the locks.

 

I just witnessed the failed alarm so I'll be watching this thread closely. Did it piss my wife off something fierce.......ooh boy........

 

Fantastic post, thank you very much.

I had an issue with my 93 300TE where I tried to disconnect the alarm, but in doing so the alarm connector came apart and I couldn't figure out what order the wires go back in (even after trying to find a pinout diagram online). So I resorted to bypassing the whole alarm system with the instructions in this post, and now the car starts again!

However, now the power locks are not working. I also had a new stereo installed, so it could be related to that... but has any else had this power locks issue? I'm back to the old days where you have to manually lock each door, it's awful!

Any help would be greatly appreciated.

 

heyguys, i became kind of fluent with these symptoms of the alarm randomly going off. in all 3 of my cases with this issue on the W124 w201 and w202, it has been a bad wiring harness chipping away exposing wires, disabling the alarm is only a temp fix, there are bigger issues at steak...

 

I recently disabled the alarm in my 94 E320, which has the starter lockout relay (found on 1993+ ATA systems). not wanting to deal with pulling the dashboard to access the starter relay, I carefully studied the ETM, and determined that I could jumper pin 1 to pin 2 on the larger connector at the ATA alarm box under the passenger floor board, and that will enable the starter relay..

 

Nice work to jump anti theft system



Is that what the "immobilizer" does? Disables the starter? Or something else? My engine cranks like crazy and I'm blaming the anti-theft for the problem, but I'm thinking perhaps the fuel relay.

 

yup, thats ALL the immobilizer does, disable the starter motor. the starter signal on the ignition switch goes through that relay en route to the starter solenoid.

here's the wiring diagram of the ATA (Antitheft alarm) on a 1994-95 E320 wagon
https://www.startekinfo.com/StarTek/outside/12264/Program/ETM/2482400.pdf

relay K38 is the immobilizer relay, located on the firewall behind the instrument panel. N26 is the ATA module itself, located under the passenger foot panel, and M1 is the starter motor.

note that N26 connector 1 pin 1 goes to the immobilizer relay coil K38 pin 5, the other side of said coil, K38 pin 4 is connected to fuse 5 and on to power circuit 15 (on with ignition or start). ignition switch S2/1 pin '50' (start) goes to relay K38 pin 1, and relay K38 pin 3 goes to the park/neutral safety switch S16/1 pin 8, P/N switch pin 9 goes to the starter switch.

so yeah, if your starter turns over, your problem is NOT the immobilizer.

 

Understood. Thank you.
Frustratingly, the car started right up this morning after sitting overnight. My brother, who is not a mechanic, guesses that eventually the anti-theft system timed out and reset itself, which is why the car started up. But if the ATA is the immobilizer, which disengages the starter, then that can't be the answer.

With respect to disabling the alarm which is posted in this thread, I am including here a photo of the same module (identical twin multi-pin connectors) which is under the passenger foot rest of my 1992 400E:
https://plus.google.com/u/1/photos?pid=5989903311691537938&oid=113683761986407393197
So the module which is previously identified as the anti-theft alarm clearly has "Becker Audio" on the sticker in my car, which leads me to believe it's part of the stereo amplifier system. Unless Becker Audio also made the ATA component.

 

can't se your photo, but my ATA is made by Becker. The one from my 1994 E320 is 124 820 56 26 [09]

 

"Step 3: Unplug those big plugs. On pre 1993 cars, this should be sufficient to disable the car. Not the case though for 1993+ cars as they have an immobilizer feature that is triggered when the alarm is disabled. so my car would not start after unplugging those two plugs."

I need to do this on a '92 ; so hopefully I can stop at Step 3. Anybody else done this on a pre 1993 W124 before and it worked?

 

i disabled the alarm on a 1990 as well as a 94.

if your car has the immobilizer, the starter simply won't crank after unplugging the ATA, and the simplest fix is to jumper two pins on one of the plugs you just unplugged as I posted months ago...

 

I have a 1992 W124 and I unplugged those 2 plugs under the passg floorboard as in Step 3 and my parking lights still flash when opening the door or while driving or when stepping on the brakes (they go off and on). Anybody know how could resolve this?

 

my parking lights don't flash at all when the alarm is armed/disarmed. Did someone add an aftermarket alarm remote system to this car?

 

Yea unfortunately, it was on there when I bought it. Can you or somebody help me resolve this?

 

remove all traces of the aftermarket crap, restore all circuits to stock.

 

I guess I'll have to take to shop, Because I don't know what all is aftermarket and who to get the circuits back to stock.

I see one red wire that doesn't look like it is stock over there near were the main alarm plugs are. But someone would have to walk me through trying to remove everything else and restore circuits.