ASR problem limp mode etc opinion needed. - PeachParts Mercedes-Benz Forum

just5 · #1 02-18-2009, 06:28 PM

I know very little about cars as I just drive them and I am stuck with a big problem. I have an S600 V12 1991. I had my battery replaced along with the battery charger (cant remember what it is called) because the battery would not charge. For the first hour or so after i got my car back I believe that ASR light was on but everything was fine and it disappeared after a while. It has been around 4 weeks now and today while driving in traffic suddenly ASR goes on and the car goes into Limp Home mode. I turned off the car and turned it back on and it was fine again. Few hours later it did exactly the same thing but this time I had to wait longer for it to turn back on.

I read all of the other posts and forums and I know that many go to their mechanic to get the error codes and some have to pay lots of money to get it fixed. I dont have money to get it fixed and I am actually in Switzerland right now and just have 2 weeks left here before I have to drive back to Germany where I live (It is 600KM which is a few hundred miles!). My question is, is it safe for me to drive back to Germany? Will I be able to make it? Should I stop driving for 2 weeks and take the bus, and then drive to Germany? I really dont have the money to get it fixed here in Switzerland so any help would be appreciated!!!

deanyel · #2 02-18-2009, 08:15 PM

It's an 18 year old car. It's ASR. No one can tell you if you're going to make it home. The astute answer is that you might and you might not. If it was me I'd consider two alternatives 1) get the codes read, or read them yourself, then reassess, or 2) develop a plan to divest the car in the next two weeks. It doesn't sound like a real good fit for you under any circumstances.

Will_w202 · #3 02-18-2009, 11:06 PM

Quote:

Originally Posted by deanyel

It's an 18 year old car. It's ASR. No one can tell you if you're going to make it home. The astute answer is that you might and you might not. If it was me I'd consider two alternatives 1) get the codes read, or read them yourself, then reassess, or 2) develop a plan to divest the car in the next two weeks. It doesn't sound like a real good fit for you under any circumstances.

Agreed to all. An aging V12 Benz is not for the faint of heart or wallet. That said, under/overvoltage conditions can certainly cause an ASR light. Finding a shop to read codes is step 1; after that, it's an exercise in logic and going from smallest/cheapest components first, unless the codes give a plain answer.

Arthur Dalton · #4 02-18-2009, 11:39 PM

If you are worried about the trip, fully charge the battery the night before you leave and use as little consumables as possible..if the fault is low voltage condition, you will most likely make it OK..
..or, if the roads are dry , you could unplug one of the front wheel sensors up near the shock towers , thereby dis-abling ASR/ABS...that will stop possible limp, but remember that you now just have reg braking and no ASR .
Personally, I would throw a voltage regulator on the alternator, just cuz it's cheap insurance and may in fact be the fault...and get the battery up full with a SLOW charge ....[ 24 hrs/low Amp]

just5 · #5 02-19-2009, 03:02 AM

thank you for the replies and for putting it in fairly plain terms. im going to go today to see if i can get the codes checked. ive read that in many cases its a progressive problem so I thought that if I dont drive the car for 2 weeks it wont get any worse and Ill manage to get to germany but because it happened twice on the first day then Im not sure anymore.

just throwing this fact out; my old battery was 100ah V12 while the one that they put in couple weeks ago is 90ah v12 from what I remember. I believe that these are the figures. Does this have any effect on it? Im not sure if this is related at all but sometimes as I start up the car and simply put on D, the car kind of chokes a bit fr a few seconds while driving min speed. It doesnt choke on start up but as you put on D and start moving the first 10-20 meters. Could both of these symptoms are related to the ASR and low voltage?

pesuazo · #6 02-19-2009, 08:21 AM

As you may know the Neutral Safety Switch is part of the ASR circuit. I have read many cases where the NSS starts going bad, and cars go into limp home mode.
A forum member (do not remember if this forum) had the same problem as yours, what he did was to drive the car in 3 and that solved the problem until he got home. The car was on running on higher RPM's, but at least he got home.
I am not saying that your problem is the NSS, but it "appears" that is the case. Reading the codes will definitely will help you to narrow it down.

just5 · #7 02-19-2009, 08:53 AM

UPDATE: I went to a mercedes dealer and got it checked out. There were no errors and the mechanic also checked the fuse etc and all seemed fine. It wasnt a full diagnosis but they said that if the problem occurs again I should come back. So what could the problem be if there is no error? He suggested that it could be just a one or two time thing that the brake did not connect in some ways which caused the ASR to go on but it was just an idea.

I also got the voltage checked and it was fine, close to the red but still on the green of the scale. They exchanged the battery though, just in case.

So any new ideas? Today when I was driving there were no problems. Im thinking that since the mechanic in MB said it was ok, and since I had no problems, that I shouldnt push my luck. I might stop driving for the next 2 weeks and then more or less safely drive home to Germany.

Ill keep the tip in mind with regards to driving in 3. I was thinking whether that would change help reduce the risk.

Arthur Dalton · #8 02-19-2009, 08:57 AM

Like I said,,the suspect is low voltage and it can be caused after a couple of weeks b/c the voltage regulator is not fully rechanging the battery.. you are fine until the battery starts to get low. So, I would look into the VR..it is cheap and a very common, wear item... and it take 5 min to change.

They checked battery condition, but I bet they didn't check changing system, did they??

just5 · #9 02-19-2009, 12:04 PM

well one mechanic simply plugged his device to the battery and checked its voltage but did nothing more. it was on the low end of the green from what I saw. So how does the low voltage explain the ASR light and limp mode if I may ask for my own knowledge?

I was also told that I shouldnt charge the battery via jumper cables to another car when my battery dies because it messes the computer ABS/ASR system in some way. I did not know that and did it anyways when my battery died a few weeks ago so this could be an additional factor to consider?

Arthur Dalton · #10 02-19-2009, 12:13 PM

What I am telling you is the car is running the battery down b/c the alternator is not fully charging it...so, the test is to check the voltage as the car is running to see what the output of the charging system is.
A low V condition effects both ASR and ABS systems.
If you charge the battery as I recomended and the fault goes away with a fully charged battery, only to return a few days later, that indicated a low V conditon. The battery can not charge itself..so you want to know is " does the ALT put out the factory specs needed to keep the battery fully changed "..if NO, the first suspect is the Voltage Regulator b/c they wear out.
Could be new batteries in there every week until the Cows come home w/o solving the problem
Check the V output of the CHARGING SYSTEM..or have someine do it ..it takes all of 30 seconds..

just5 · #11 02-19-2009, 12:19 PM

alright thank you, it sounds like very sound advice. had the alternator exchanged with the battery a few weeks ago because it ended up being the alternator which was not charging the battery. Ill get the voltage regulator checked out. Maybe this sounds stupid as I know literally nothing about it, but I would assume that a mercedes mechanic woul dhave checked this part too while they change the alternator.

Arthur Dalton · #12 02-19-2009, 12:23 PM

If they changed the alt, then forget about the Regulator..it is a part of the alt...but I would still have the new alt checked for output. They may have already done this and you just did not know it.
Ask them what is the output of the alt.

just5 · #13 02-19-2009, 12:28 PM

so the chances of it being the regulator are slim now eh... ill get it checked out. thanks once again. If it is not the regulator than what else could cause this to appear twice without any code errors?

Arthur Dalton · #14 02-19-2009, 01:00 PM

Could be a hundred different things....but the first thing to check is charging system b/c you had a battery problem coupled with asr lamp. So that indicate low V condition..that's all..it is just the FIRST thing to check before you go guessing...

jayauto · #15 02-19-2009, 06:21 PM

I didn't think the 600SEL came out until 1992, you cannot read asr codes with the impulse counter until 1993-94. you must do pin tests, voltage / resistance etc.. codes with a scanner / impulse counter are only for diagnostic module, engine, abs and throttle actuator. The problem is probably the throttle sensor of the actuator but testing without known good part substitute is time consuming. We would charge 4hrs to diagnose the asr system. Be very careful with charging system problems and address them fist. Check the connection of the smaller wire at the battery positive cable end at the battery, I have seen other shops loosen this when changing a battery (it doesn’t need to be loosened) and then forget to tighten it. Good luck with the repairs, make sure to post what your ultimate fix is.

Jason Athanas
Autobahn Performance Inc
Ft.Lauderdale Florida
Jason@autobahnperf.com