DIY ASR Defeat Switch
 

vcci wrote
I thought it would be great to start a unique thread on this topic so that any/all who are interested could easily find the info.

vcci, the floor is yours

Dear vcci & aldedmon:

By all means please post or email to me instructions on how to build an ASR defeat switch.

I want to rid my car of ASR and have a limited-slip differential installed. So far, Renntech estimated that this mod. would cost me $3K at their shop, but if I defeat the ASR first, their price should come down to $2K.

Thanks for all your help.

The limited slip diff is expensive if you have ASR because there are components inside the diff that support the ASR. If you "defeat" the ASR it will still be expensive to install the limited slip because ASR is still there, it's just not operating. You could fit a non ASR diff I suppose.

Matt.

Ok this is the deal. I am not too familiar with the electronics of cars but I will do my best to tell you everything I know.
After searching this site for about 2 weeks trying to figure out why it costs almost $1000 to get this damn ASR off in my car I ran into a post that showed a diagram of the ASR defeat system and the way it works. I also found complete instructions for installing the ASR defeat made by RENNtech and had a friend of mine take a look at it. After just a minute of looking at it my friend says "this is a piece of cake, how much did you say this costs?" 20 minutes later he tells me to take it for a spin and see if the wheels are spinning, and guess what, those tires were burning like no other benz ever burned. What you need to do first is find the installation instruction posted somewhere on this site, I cant find them again for some reason. Now, find the box located near the firewall on the driver's side being help by 4 allen screws, remove the the complete box, find the computer named ASR and remember what slot in went in to. If you look at the instructions it will give you colors of the wires and numbers, all my friend did was disconnect those 3 wires. This will completely turn off the ASR the car will burn rubber like you wont believe. Please excuse my limited knowledge of the process. My friend now made for my car a box with 3 modules or relays ( i dont remember which ones he said but I will ask him and post again) located inside, he will connect a switch to the box with modules or relays and I will be able to tur the ASR system on and off. I was gonna buy an original W140 ASR switch and put it on the panel next to the snow chain switch but I figured having it mounted under the steering column would give me an advantage of having it off when I give to my wife to drive and not having her mess around with too much power for her to handle. I have been driving the car for about 5 days now and can tell you that this has completely changed my views of te 500E, it is simply a 4 door porsche, amazing performance, a sedan like no other etc. I have read posts regarding the ASR defeat is kinda like keeping the snow tire chain system engaged for higher speeds, NOT TRUE, the wheels are still being kept from spinning. The ASR light has been on since this was done but I'm sure it will turn off after my on/off switch is switched to off. Let me know if you have any further question and I will try to answer them the best I can or I will ask my friend and get the right answers for you. ANYWAY SORRY FOR THE LONG POST BUT IT SURE BEATS PAYING ALMOST $1000 FOR SOMETHING SO SIMPLE.

vcci,

Does diconnecting these wires affect the ABS System?

NOT AT ALL

vcci:

The ABS and ASR work off the same speed sensors, so my understanding is that if one's offline, then so is the other. Have you actually invoked ABS with a panic stop or two? Please let us know

Also, I was not able to locate any box on the driver's side as you mentioned - can you post a picture or more detailed instructions on how to find it? Thanks in advance:)

I have not envoked the ABS system but I will later today and post results, although I am pretty sure the ABS is functioning properly. The box I was refering to is on the passengers side next to the firewall.

Here is one of the threads referenced in vcci's post
 

RennTech Diagram
http://www.peachparts.com/shopforum/showthread.php?threadid=26660&highlight=ASR+defeat

Thank you Aldedmon for posting the instructions. As you all can see this will walk you through the steps of how to defeat your ASR.
NOTE: While looking for the wires at the connection of the ASR computer control unit we noticed that the colors were not as stated in the instructions, my friend went by the wire numbers and they were correct.
So far I have not had the switch installed in the car but if you just want ASR off this will do it. I will keep you informed after the switch has been installed.

That's the CAN Bus. I'll check it out (and the 4 allen screws simply hold the cover on-must pull the appropriate module out)

has anyone tried it? i'm just wondering if anyone tried it what they thought and how they liked it. I personaly love it.

DIY ASR Defeat
 

I do have a very good understanding of electronics, as I deal with them on a daily basis, I can read electrical/electronic drawing easily and I think that something like this will work perfectly. I've recently been doing my own research on how to defeat the ASR on my '97 C36 AMG, while I haven't read completely through this thread my first impression is that it is probably very true. I've found some technical data that states that the ASR is completely disabled when the stoplamp switch(S9/1) is engaged, this is the switch that is actuated by the brake pedal - turns brake lights on and off. It is a 4 pole switch with 2 of the poles going to the ASR control module (N47-1). So as the brake pedal is pushed it defeats all function of the ASR, but natrually it lets the ABS function fully. My theory is that with some simple rewiring of the ASR switch, one could "trick" the ASR control module into believeing that the brake pedal is constantly applied, and TaDa... no ASR, and no trouble with ABS. Making it switchable means one can have all the benefits of ASR, but also turn it off for more fun. I have not had the time to try this out yet, and as it is the dead of winter here where I'm at ASR is greatly appreciated. I'm planning on trying it out this spring. I don't know if this is the same conclusion/method that vcci is using but I know it can be done. Post back if someone wants more details on my theory... good luck.

More DIY info
 

After looking at the info in the thread more closely I'd be very careful while making modification like this, while I'm sure it works as advertised I'd be cautious. According to the information and drawings I have the wire/terminal #'s of 25, 35, and 37 per the RennTech instructions are for the ASR/ESP/ETS hydrualic unit. I'd be VERY careful messing about with this unit and it's wiring/control. I do know that there are (2) different versions of the the ASR control module (N47-1) and I know the drawing I'm looking at is for my 1997 C36 (W202). So maybe those wire/terminal #'s do apply to the 500E series of cars, but I'd be careful of trying on a different model without some research. I'm not trying to burst anyone's bubble, just a word of warning... Good luck.

Tifosi
I don't know if this would work for the C36 or not but if it can be don on the 500E than I would think if one found the diagram for the C36 it would work just as good as it did for my 500E.

ASR Defeat???
 

Vcci, thanks for the reply, I also mispoke (wrote) there are at least 3 versions of the ASR control module (N47-1) instead of just 2. I believe numbered; SK 16, LK55, and LKS511. I am also now doubting my previous theory with the brake switch, I believe this would throw the ABS into convulsions. So back to the drawing board for me. If someone could cross-reference what terminals #25, #35, and #37 are on the ASR control unit are used for on the 500E maybe I could find those on my ASR control unit. Thanks again.

sorry TIFOSI I wish I could help but as stated in my earlier post I am not very familiar with electronics and that why I had a friend do this for me. As I said before this has not interupted with any other component other than the ASR and I love this set up much more than the original set up.

I'll pose this question to anyone who might be able to help...
According to the RennTech directions posted, the RennTech module connects in between terminations #25, #35, and #37 on the ASR module. I'm assuming these are based upon an older version of the M-B ASR control module housing SK 16, or even the LK 55 type. My C36 has a LKS511 version of housing. I'm assuming again that the terminations must be different on these housing styles, as that the #25, #35, and #37 terminals on the diagram for the C36 are for; #25 - hydraulic pump runnnig check; #35 - left rear axle solenoid valve [hold]; #37 right front axle solenoid valve [release]. Best as I can tell adjusting, interupting, or anything else to any of these particular circuts wouldn't accomplish a damn thing other than screwing up the works. So if anyone has a diagram for an older version ASR control module [SK 16 or LK 55] and can find out what terminals #25, #35, and #37 are for, maybe we can reverse engineer our way into how RennTech is defeating ASR. Granted we won't know what exactly their defeat module is doing, I'll bet we can figure it out, and do the same thing for less than $1000.

To everyone waiting for the final result of my ASR defeat.
I finally completed my ASR defeat today when I had my friend install the switch, everythig works perfect, I can turn it on or off as i desire while driving or at anytime for that matter, I dont need to restart the car in order to reset the system. This has in no way effected my ABS system or anything other then my ASR. It works perfect and I'm 100% glad I did this. NO REGRETS.

For anyone interested in having it done, I have talked my friend in to doing this for others( for a small fee) so if you're interested drop me a line.
Thanks and Good Luck to all.
Asi

Some reasonably detailed instructions would be great...maybe a diagram or three? :)

In this post i tried to explain in great detail the process. In this post you will find a link to the diagram and instructions. Hope it helps.

Thanks...I mean, a diagram of the relay/circuit your friend made for the switch. :cool:

How small a fee
 

Lets see
Gas to Drive to Encino and back (2500 mi div. by 400mi/tank X 23gal tank x 1.75/gal) = ~$300(I hear gas is as high as $2.25 for Premium unleaded on the west coast:eek: )
Payment of ticket(s) to State law enforcement agencies of Texas,New Mexico, Arizona, and California = $500
vcci's friend installing modified ASR switch= "X"$$
Not having to deal with the annoyance of undesired traction control.....PRICELESS!
:D

Its looks like as sweet as the prospect of vcci's friends ASR defeat switch sounds its just cost prohibitive for me here in the Lone Star state. Gas/Hotel alone would dang near put one in my hands from bergwerks and I don't have to do all that driving to boot. Not that it wouldn't be one hell of a drive though. Maybe when gas goes back down to a respectable level (sub $1.60) I'll think about it some more. But for now, I'll just have to keep dreaming.

Lastly
Hey vcci, could you be a pal and take some pics of your setup. I think those of us who might be skillful enough to attempt this surgery, would be a lot more confident if we knew exactly what wires to splice into from a pictures perspective and where / how to then hook up the switch.

I would be glad to post some pictures but unfortunately pictures wont show much. I fact the relay box he put is behind the computer box and it is impossible to show anything in the picture.
The was placed next to the headlight switch. Here is a picture of the switch. sorry i couldnt be more help.

Here the ASR is turned off.

I'd love to come down from the Bay Area, get the Bergwerks first gear, then the ASR over-ride. Is your friend serious about doing for others?

Tom
92 500E

Absolutely 100% and let me tell you, he is the best. I couldn't be happier with my defeat system. Drop me a line and we'll arrange something.
Asi

Is he interested in selling the diagram or the box itself...?

I'd have a bit of a problem driving to him...... ;)

Easier way?
 

I just defeated ASR in my 500E. What I did was to simply identify pins 25, 35, 37 (there are 2 sets of pins with each of these numbers, so I took my CAN apart & based upon color-coding was able to ID the correct pins; they're the set closer to the centerline of the car) on the bottom of the ASR module, then I took some postal tape (a bit thicker than your typical Scotch tape) and put a thin slice of tape over the pins. Thus, when you slide the module back in the connections are interrupted!

Just thought I'd share - done this way it's a 10 minute job and really easy!

Gonna go do some burnouts now...:D

Way to go.

Anyway to get a diagram of this Michael?

I've been avoiding messing with the idea of defeating the ASR but heck, if it's that easy who can resist. With a simple relay going off the wires you mention and the other side hooked up to a console switch you have a $30 (max) DIY ASR defeat.

Thas what I've been trying to tell everyone. Hope you all succeed.

FWIW I was reluctant to permanently mess with/cut into the wires involved this time around, since they did NOT match the color codes cited by RENNTech. However, obviously the wire #s were right, 'cuz it got the job done.
Ross/All, here's what you do-pull your ASR module out, and figure out which 2 rows of connectors are closer to the centerline of the car, when installed. That done, look near the pins (on the module) and you'll see their identification #s. Put thin tape over 25, 35, & 37 and then re-install the module (I also put a tiny dab of grease on each to ensure they'd slide in easily w/o damaging the tape). Pop the lid back on the CAN and you're done!

I may indeed do a permanently installed switch sometime, but it is sort of a bear to get that upper aluminum CAN box separated from the lower part and out of the car - if you don't have all the right hand tools you're gonna have a tough time:(

PS I just boiled the tires thru 2 gears:)

I think we understood what you were saying. I was hoping for clarification on the switch/relay needed to safely turn ASR off. I'm hesitant to just install an inline switch...

Can your friend provide a diagram to help us build a proper relayed switch? :)

the box that RRENtech sells only has 3 relays insode. All you would need is 3 relays connected to a switch which can cut or give power to the ASR. Thats all I can tell you. As I mentioned before I didnt do it so I cant give exact instructions, sorry. Hope that helped everyone.
Asi

Thanks...any info at all is helpful. :)

vcci-

Thanks for your help! Should've said that in my earlier post:rolleyes:

before installing the actuall switch I was running the car with the ASR disconnected for about 3 weeks, never had any problems.

Which brings us all back full circle to....
 

Your fiendish friend ...Young DR. Frankenstein. whose engineering masterpiece has us all salivating so. You keep saying you do not know what / how he did it. So what's it gonna take to get this guy a computer and a digi cam so that we can finally get some answers.......:confused:

My E-Class Owners Bible also suggests you can simply jumper sockets 6 and 1 on the diagnostic plug together and this will disable the ASR/ABS module.

The ASR/ABS warning lights will come on and I suppose a fault code will be registered.

Dean, restating the obvious, won't that disable the ABS as well as the ASR? I'm not sure I want to do that. I like having ABS handy, just in case...

Tom
92 500 E

Too true Tom, you'd lose both ABS and ASR. But, for a temporary shut down to have some fun or run the car on a dyno, it could do the trick.

Dean/All,

Jumping pins 1 & 6 throws the car into diagnostic mode, and kills both ABS and ASR, lights the dashboard idiot lights, and stores a fault code (I think). You can do the same thing by simply unhooking one of the front wheel speed sensors...same results. However, what I've done just shuts off ASR, but does light the ASR dash warning light. Oh well.

That was not the case when mine was done. Only the ASR was effected and not the ABS, ABS was still working normally.

My friend has been out of town for the past couple of weeks and will not be back for another three weeks or so. As soon as he is back I will find out and post further instructions. I just don't understand how nobody here can figure it out, it seems there are many knowledgeable people here. He was able to figure it out just by looking at the diagram. I wouldnt be able to figure it out if my life dependent on it, but it can't be that hard if one is familiar with electrical. Anyway I will post further info a soon as he is back in town. Maybe someone can figure it out before then. Hope it helps and sorry if it doesnt.
Asi

No Need to feel sorry
 

Asi,
You have given us all hope , the light at the end of the tunnel if you will. Surely we know it can be done and many have done it to a greater or lesser degree. But your setup seems to be the best compromise (between the high $$ Renntech switch and other pin jumping code storing methods) that has been listed on this forum to date. Our(My) frustration is that we(I) want what you have , but have been unable to copy this seemingly simple process. Bear with us(Me).Because as soon as we do figure it out, we can ALL then enjoy the raw, unadulterated pleasure of making these beasts beg us to ease up on the right foot. Thanks for taking the lead on this mod. and finding an inexpensive way to do it that works!

C'mon, this MUST be pretty easy to do. I mean, all I did was interrupt those 3 connections. So, if you install a relay (or rather, 3) that can be made to open or close these connections at will, then you're done. I'd think a trip to Radio Shack and you're done.

Austin (Omegabenz) sent me a copy of a 1992 article on the Renntech E600 conversion. Interestingly, Fehyl suggested their best launches were obtained by activating the "snow chain" switch which disables the ASR until about 20mph.

I've tried it out, starting from 1st gear, and it does allow a few seconds of wheelspin before everything hooks up. Strangely, when I looked in the rearview mirror, traffic was waaaaaay behind! ;)

ASR on-track
 

Made a HUMONGOUS difference. I just spent the day at Lime Rock, and my car is SOOOOOO much more track-able with ASR asleep. Made for a really great day! Too bad I was in the fastest run group, since I spent much of my time pointing people by! :rolleyes:

I'm going to try and slip a 1997 C36 in with all of you 500E guys... I'm still stuck on the different versions of the ASR/ABS/CAN control modules... black box... whatever you want to call them. I have a detailed skematic of my C36's, and the three pins (25, 35, 37)referenced by both RennTech and all of those who've defeated ASR, make NO sense. But that is on my "newer/different" ASR box... I assume? Even so does anyone know what the 3 pins (25, 35, 37) reference on the 500E ASR box? If so I can try and find the corresponding functional pins on mine, then share it with the world - FOR FREE!!! I JUST WANT TO HAVE CONTROL OF MY DAMN CAR!!! Sorry for the rant and rave - I just really want to lose the "nanny". As always any help is greatly appreciated...

Picture
 

Michael, Can you take a picture of the pins and post them. I'd like to do this process. I have a line on a shop here (2 actually) that can hook me up with a switch and tie all this stuff together. Both are race shops, One porsche and the other Viper. A picture of which pins and an explanation of what I want and I'm sure these guys can get the job done

Hi guys, just been listening in on this conversations. On my 1991 500SL do the same instructions apply? From what I understand after accessing my ASR module I should somehow disengage wires 25, 35, and 37.

Also, I am good at wiring stuff, etc, but dont have much real knowledge of electronics, ie: I am a good monkey. I am assuming that the 3 relays you attach to each wire then attach those 3 relays to one switch that turns on/off the whole shebang, correct? If someone can suggest specifically which relays to buy from radio shack.

But the most important question is would this work on a 1991 500SL?