Razosman

Hi

Where to start? I have a 2004 Mercedes SL350.
The original issue I had with the vehicle was the red battery light which lead to a new battery control module.

From here Ive had a huge amount of issues.
ive had the dashboard going nuts. Every 10-15 seconds it’s alive and then dies with every warning light flashing. It does come back on like the car has been started up again.

so far this car has had
- every Sam unit brand new from main dealer fitted and programmed correctly
- new alternator
- new battery control module- water ingress

now according to the star machine the front drivers side Sam isn’t connecting however once the rear driver Sam is disconnected it connects.

on some occasions it connects to everything perfectly. Something is shorting the dash or the front Sam’s but I have no idea what. Any help would be great.

my next step is EIS? Or replacement dash?

£1800 in so far and no idea what to do. Before replacing everything I only had a battery issue and now the car has just gone nuts.

matk

Have you changed the Consumer Battery in the boot/trunk? I experienced a lot of that when my Consumer Battery was on its way out.

A1EK

I had the issue with all the lights flashing on randomly on the dash, for me it was because I seldom used the key as I have keyless go. I started to use the key in the ignition every other day and not had the issue again.

Razosman

I’ve had that checked and no issues with it. 2 different people said the battery was perfectly fine.

Razosman

So the key can cause that sort of issue. I was unsure if it could. As I’ve changed all the Sam units I know I’ve ruled out a faulty unit.

m60kaf

Water in the can connectors under the passenger floor (driver floor if you're American)?

Razosman

floor is completely dry. The car was perfect until I had a red battery light. Battery control module was completely destroyed by water. After the BCM went in the car just developed further faults.

Ghostty

Razosman,

To me that's 99% EIS module, especially if you say dash lights go nuts. No dealer will point to that since he sees that unrelated. It solved the problem on mine and many others. Basically the EIS module is connected to all the modules of the car, and whenever you start the car it checks to make sure everything works. If the module starts going bad, it gets faulty readings from all systems. When mine went bad I had no radio, headlights and power outlet working either. Was something else along with it. The bottom line is that since is connected to every single module of the car, it's hard to find 2 identical cases of faults, it can trigger any light. The dealer did not agree with me but still replaced the unit, and ended up being the correct choice. Hopefully that solves your problem too, since it's not that common... I replaced mine almost 5 years ago, no issues since.

Here's the post if you want to read about it.

https://mbworld.org/forums/sl-class-...t-nowhere.html

MikeJ65

There is a chart in WIS for the conditions under which the test pattern is displayed. The most likely causes are loss of rpm signal from CAN C or loss of circuit 15 voltage signal at the cluster.

Frederick NL

Your troubles are pointing at EIS, as others explained above. Trouble in the car: all these sorts of gremlins. Trouble with the dealer: they never seem to find it using their diagnostic tools. A defective EIS, being the digital supervisor of your SAM’s and electric components, apparently blocks proper diagnosis as well. It’s a shame and a blunder when a dealer once again starts throwing expensive parts at a car, solving nothing, at your expense. You’d probably do best refusing further costly diagnosis and ordering an EIS. If and when that solves all your trouble, I’d be inclined to demand compensation for the wrong and useless repairs they provided before.

Razosman

so I’ve had the EIS checked today and turns out that is not the issue. Not to sure what to do next.

Razosman

So far here’s the update

- swapped the EIS out and made no difference.

Next step would be dashboard however I got a feeling that’s not the problem. Something keeps knocking the front drivers Sam unit off every 10-15 seconds.

MikeJ65

When you say 'knocking the front drivers Sam unit off every 10-15 seconds' do you mean the the module is losing power or that it is not communicating?

m60kaf

Isnt the point of can bus connector noded to disconnect pairs from the bus - whatever method you want , one at a time or everyting barr 1 and keep addid til a module doesnt function correctly

The reason I mentioned wet undercarpet is the bus connectors get wet, rust and you get poor connections that cuase these kinds of problems, check the CAN connectors still stands as a check

Dont ovelook earths neither ... Ever watch South Main Auto.... Its ALWAYS the earth lol

Razosman

Sometimes the front drivers Sam will connect to the star machine and sometimes it will not. We disconnected the rear drivers Sam unit and the front drivers Sam then connects. When everything is connected the front drivers Sam will function but then lose connection.

i’ve been advised to put a new battery on the car regardless if it seems to functioning properly. When doing this I’m going to check the earth connection also.

if anyone else has any other suggestions then please do offer your advice.

super frustrated at this point. Owned 3 Sl’s r230 and never have I ever had an issue this serious or puzzling.

MikeJ65

1) Have you read all of the codes with DAS or a close equivalent, not a generic OBD-II scanner? Start with any current codes for the ICM, BCM, EIS, and SAM modules. If you only have stored codes, clear them and see if any come back. I would be especially interested in any voltage or CAN related codes that are current or return quickly after a reset. I would be shocked if you are code free. You have to be careful on interpreting the codes, but they are absolutely the place to start. If you have persistent CAN B codes, start by exposing all three CAN bus connectors, remove all wires, check for corrosion, reinstall one or two at a time while checking CAN voltages. If you have any persistent low voltage codes, check the power connector and the ground point for that module for corrosion. If it is low voltage across several modules, trace the common power feed back across all connections and fuses as well as the battery connections and ground.

2) I would look at the voltages on the passenger side SAM and monitor them for awhile. You can see circuit 15 & 30 voltages and circuit 61 high/low (alternator charging or not).

3) If you are not getting any DAS communication with the driver's side SAM, go to the AAC module and check ambient temperature. The ambient temp. sensor is read by the driver's side SAM and sent on CAN B to the AAC. DAS communicates to the SAM and several other modules through the EIS. Just because you can't communicate with it through DAS doesn't mean that it isn't working and communicating with other modules.

4) It sounds like you have already replaced at least 4 good modules, don't replace a good battery as well.

5) Since this all started with the BNS replacement, double check that everything is properly connected and the that bolted wire connections are tight.

Razosman

Hi Mike

thanks for your suggestion. I’m picking the car up from the guy who checked my EIS.

what I will do is plug in the car to my machine and give you the fault codes. Hopefully that might shine some light on things.

I will probably lift the passenger carpet and double check the connections there again.

I’ve got a friend with a couple of new batteries hanging around so I’m going to try see if that fixes the problem.

I also forgot to mention the car battery will die after 3/4 days of sitting if that’s any help. Of course the car isn’t being driven with the current issues.

I appreciate all the help everyone has given. Thanks

regards

Raz

MikeJ65

Post the codes when you get them, especially the ones the won't clear or come back quickly. Since your battery is draining, you will have a lot that are just a result of low voltage. If you have an amp meter, check the current drain when the car should be sleeping. Also, I didn't look at you location prior to my previous message, so some of the driver's side/passenger side items may be reversed.

Razosman

Hi Mike

no matter how many times I clear the codes this is all I get. Photos below are from drivers Sam(rhd) and passenger Sam.

Razosman

Hi all

update

so fitted a new battery. The only errors showing now are from the front Sam which is brand new. I will attached the photos below.

Ghostty

I'm a bit confused about what you did. You stated that you swapped the EIS? Is that with a new one or used one? Was it coded and updated properly? Just want to clarify...

Frederick NL

Agree - you can’t just swap an EIS just like that. They’re ‘married’ to a single car and need to be coded.

Razosman

I sent the car to a specialist in Birmingham who tested it and confirmed with didn’t have an issues with it. He fitted a unit he had and coded it and still had the same issue. Everything that is happening seems to show an issue with the front drivers side sam.

sorry for the lack of clarity there. Currently have no idea what to do apart from work backwards and clean all the connectors or check if there’s any broken connections. The drivers Sam is showing now but seems to be packed with faults. All of these units have been brand new from main dealer. I’ve had a friend with the star machine making sure that the units are coded up properly to tell the car it doesn’t have any additional features. Very confused right now.

- changed every Sam unit.
-BCM brand New changed
- tested EIS and changed for new unit but no change to symptoms
- new consumer battery

I’ve checked passenger footwell for water but bone dry. Might consider checking all connections properly again.

Any other ideas welcome. Summer is coming soon and ideally want a working car 😂.

apart from the dash the car drives a dream.

m60kaf

So the "specialist in Birmingham" couldn't find what was wrong with it? They checked the CAN?

Dont know what year your car is but after approx 2004 the CGW handles the Body Can, Can C Connection. I'd be looking at Body can front to rear

You have Star and and a £3000 Autel and have thrown loads of parts at it and it's not fixed. You aren't likely to find your solution on the Internet.!

Trying to be more constructive though If your EIS has a setting something along the line ZGS=ein then the Gateway does the bus handling I belive. Do not change the CGW!

Also please advise roughly what is the ACTUAL running problem from the point of view, you're a punter taking to Mercedes how would you describe the current driving problems with the car. Also reset every single code in every module and list off the CURRENT! errors and what module they are in.

Likewise "I also forgot to mention the car battery will die after 3/4 days of sitting if that’s any help" doesnt make any sense that doesnt happen on an R230 specifically what do you mean by battery will die

Razosman

Thanks for your input.

My car is a 2004 Mercedes Sl350.

so the guy I took my car to is a guy in Birmingham(Uk) who looks after Mercedes keys and ignitions. I’ve taken a couple of cars to him and trust his work.

so the actual problem is when the vehicle is running the srs light will flash, along with the red brake light before the speedo shutting down and restarting and going back to normal. This happened every 2-3 minutes sometimes a bit longer.

no matter how many times we reset the fault codes we are getting the same codes come back stored. All STORED codes are being reset and coming back. The only one that doesn’t change is the b1076 which is current and stored.

In terms of the battery issue I believe that this was down the car not being driven as much because of the ongoing issue and the battery not being fully charged.

I know I have spent a huge amount of money but that was me following the star machine which I’ve now given up hope in at the moment.

The most constructive thing I’ve come to so far is that the front drivers Sam has a connection issue and that’s the cause to my problem. So next step would be check all the wiring to the front drivers Sam.

does anyone know of a good auto electrician in the (UK) West Midlands area. Don’t mind travelling if it’s further.

As said before I appreciate all of your inputs.

if this doesn’t work anyone want a free Mercedes sl350