Definitely something is happening on the can bus. Have you scanned for codes with INPA or ISTA? You could start unplugging modules to see if it goes away and then identify the problematic module. I have seen a few Youtube videos for monitoring the can bus but they usually use oscilloscopes, which I do not have. I would like to know why your mechanic thinks SZL. If he threw that out there though, it's worth starting there by unplugging it to see what happens. Remember that everything is interconnected and an electrical problem like this could be caused by a whole long list of things. Disconnecting the battery restarts these modules and perhaps it takes a while for a defective unit to start freaking out.

 

You could start unplugging modules

I wouldn't even know where to start.
I think that he thought SZL because it effects the Steering Wheel Controls.
Is there a list of Can Bus Modules.
I think I have an oscilloscope though I would not know where to connect it..
Plus
Even if it is a Can Bus problem why would it not be present all the time?
How could a Battery Reset cure the car for Weeks even Months before recurring?
Before now that last occurrence was before Thanksgiving.
That's 7 months and now it's back.

Could it be battery related?
I had it at BMW for a couple of Recalls and they said that the car had some "Low Voltage" related errors.
Could the battery possibly dip below the car's needed voltage and then a Can Bus or other error trips.

I don't want to spend the $$$ but maybe the next time that it happens I just drive the car to BMW and let them have a look at it.

I have already invested over $5,000.00 in repairs and general upkeep.
Valve Cover Gasket, Oil Filter & Cooler Gaskets, Water Pump & Thermostat, Transmission Mechtronix, AC Repair as well as new Tires & Alignment

Might as well not stop now.
I was hoping maybe someone else experienced something like this.

UPDATE:
Checked Battery Voltages this morning after sitting overnight
Pre-Start: 12.34 Vdc
After Start: 13.94 Vdc
Volts look good

 

UPDATE:
I have been checking the Battery Voltages and it has been constant at about 12.34 to 12.37 each morning.
Then once the car is started the voltage is solid at 13.94 and no matter if AC is on or off
Last time I had to reset the car via battery dis-connect was Wednesday May 25th so today June 8th marks 2 weeks.
As I said once before this non-reset period lasted 6 months....I'll see how long this period lasts.
I wonder each morning if today is the day or not because if it's going to happen it's a few minutes after I start the car for the first time of the day.

It also seems that it occurs more if the car is not driven for a day or more but if driven daily the car behaves itself.
That's why I thought that maybe over a few days the Battery voltage would drop below a certain voltage threshold and the car would have a hiccup.
At this point I'll keep monitoring the car and see if I can discover a Cause & Effect.
If it happens and the battery voltage is the same at 12.34+ them I'll know it's probably not battery related.

 

How old is the battery? I had something similar occur when my 550i sat for a number of days during the colder weather......certain things (i.e. the dashboard) would shut down. I purchased a battery charger and that kept the battery maintained when the car sat for a few days. Now that the weather is warmer, I find that the charger isn't required if the car sits for a few days. Basically, my battery, although only 3 years old or so, is becoming marginal. Perhaps yours is also.

 

3 or 4 years is about all you can expect out of a car battery here in (hot!!!) Arizona. That said, the battery in my E61 was (IIRC) nine years old when I swapped it, though it was pretty tired. I suspect it spent most of its life garaged (before I got it).

 

Bud B,
Since the issue is intermittent, I recommend you start by checking the ground(s) associated with SZL. These cars are hyper sensitive to ground issues; which is understandable? Watched a video last night that showed a no start condition caused by a fried DME due to disconnected fuel injector grounds.
Good luck
Fred

 

First off thanks for the replies..
UPDATE:
I was off from work so my car sat for a day and I did not drive it.
Actually from 3pm Wednesday to 11am Friday the car was not driven for 44 hours.
I did think about running it around a bit on Thursday but I was just too busy.
Before I started the car on Friday morning I checked the batter and it was at 12;18 volts.
When I am driving it daily the battery rests at 12.27 volts.
It does not seem like a huge difference but it was enough to trigger the event.
I started the car and within a few minutes the "Cruise Control" error popped up and the "Windshield Wipers" started doing their dance.
The wipers stayed on all the way to work.
When I got to work (about a half hour drive) I disconnected the Negative Battery cabled and strapped down the trunk lid.
When I got off from work (5 hours later) and I connected the battery (12.28 volts) everything was fine again.
Set the time and off I went.

So I have driven the car everyday since the last time this happened on May 6th. which was also a Friday
I'm off every Wednesday & Thursday. and I did not drive the car on Thursday May 5th.
So that's the routine...Don't drive the car for a day and the event will happen.
I would probably bet that if I did not miss a day of driving the car would be fine

So my thought is:
Drive the car every day to keep the Battery up to at least 12.27 volts or think about checking and probably replacing the battery.
I did have the Alarm on for the 44 hours...maybe that was enough to drop the voltage to less than the usual 12.27 volts.

This is so weird! LOL

How old is the battery?

Could be 3 years..maybe 4 .
It's a Wally World battery.

 

There should be virtually no change in anything between 12.27 volts and 12.18 volts (or even 12.00 volts). Did you try to monitor the battery voltage with the car running? Is it possible that the voltage is too high? That can cause issues.

Otherwise, I'd suspect the modules that are associated with the components that are acting up.

 

"I think I have an oscilloscope though I would not know where to connect it". If in fact that you do have an oscilloscope, you want to connect a channel to each CANH (+) and CANL (-). Then you can monitor the CAN traffic. I don't recall the CAN specifications in any great detail, but I seem to recall that if a unit detects a certain number of self-forced errors, then it will take itself off of the network (or something to that effect). If this is the case, then I assume that INPA, etc, would not be able to communicate with it and would show the module as a dead link. I also assume that this would set off an error code or two.

 

UPDATE:
The Occurrences of:
Cruise Control Error, Wipers Run, All buttons on Steering Wheel are In-Operable, Steering Wheel will not raise or Lower, Rear View Mirrors on doors will not adjust via driver door controls, power steering out, overhead light stays on rather than dim down and out after car start.
Let's see any other crazy occurrences..a few

So my Mobile BMW Mechanic came by to check it out.
His assessment is that it's the SZL Module at the Steering Wheel
He would try and reset it and he could not communicate with it at all.
This is the Svc Scan Results in PDF
My apologies for his poor printer pages.

He has ordered a used module ($180.00) from Europe due to arrive August 18th and we will see what the status is after it's installation.
I will Update the cars results Post it's Installation.

FYI: He did remove the 30 amp fuse #16 (in glove box) that controls the Wiper Relay so at least the Windshield Wipers do not run continuously.
I felt like an idiot driving my car on a perfectly Sunny Day with the Wipers running.
Now if it rains I will have to pop in the fuse for the duration.

 

UPDATE:
My Mechanic came by and installed the used SZL / Switch Unit into my Steering Column.
Like my Original SZL he cannot communicate with it
Hence the Used one is also bad.
He has only charged me $100.00 each time...First to Diagnose and then for today.
He is also eating the $180.00 cost of the used part.
I offered to buy it or at least split it with him but he said no.
When it comes to Mechanics he's been really good.
Truly hard to find these days!

He is sure that it is the SZL / Switch Unit Steering Column 613010 - (61-31-9-136-898)
We just need to find one that he can communicate with to program.
Which also poses a problem with programming a new SZL to the car as he cannot download the program that was in the original working SZL so he will have to do it manually

I can pick up a new SZL From a local BMW Dealer for $525.00
So forget the used parts method just to unreliable.
I'm going to purchase a new SZL and go for it!

Another update to follow for this Saga

 

UPDATE:
I really do not know if any of this will help anyone else should their care experience an error such as mine.
I hope so...
I decided to once again...dis-connect the Negative side of the battery and let the car drain down overnight.
The next morning I(yesterday 08/17) reconnected the batter and everything with the car functioned perfectly.

• The steering Wheel buttons, Side Sticks as in Turn Signals, Cruise, Wipers & Horn as well as the ability to move the column up and down.
• Power Steering "Power Assist" fully returned.
• Door's Side Rear View Mirrors Functional again.
• All Power Windows are functional again.

So I met with my mechanic this morning to do a scan.
Where before he could not communicate with the SZL today he could and downloaded needed info (if ended) from it.
Whatever the issue is.... A Battery Disconnect / Power Drain will Reset it and allow everything to function again.
I can tell that my mechanic is a bit mystified over the issue and is something that he has never seen before.
I asked him if he had ever seen what looked like a dead non communicate able SZL after a power reset function and communicate fine?
Though the SZL is still not without I think 11 errors.

Sometimes things like this are: "Can't see the Forrest for the trees".
It could be a hit the side of your head so simple and gives a "Why didn't I think of that before" or really is a very complicated Service Issue.
Sometimes a new set of eyes will help.
We are yet to discover that.

 

Rather than a $35.99 work around would you spend Thousands to BMW to repair the same thing on a 16 year old car?

I have thought long and hard about my predicament with my BMW.
My car seems to have an evasive Computer / Electrical troubleshooting nightmare!
Makes me hanker back to when cars were so much simpler and not so much computer driven.
Do we really need the extremely complicated computer based cars of today?
I mean....you turn it on...there are headlights, brake lights, turn signals, a radio, same thing my first car a 1954 Studebaker Lark iV had
Then my Oldsmobile Cutlass, (man I liked that car) granted none of them had Power Windows, Powered Seats.
or Cruise Control.
Still does my car need more computing power and sophistication than that that launched the first moon rocket or Lunar Lander?

I am going to take my car to the local BMW Dealership and spend their $329.00 Diagnostic fee to try and find out what ails my car.
However IF the solution is in the thousands then I am seriously thinking of installing a remote control battery disconnect. (watch the video)
Amazon.com

Then each nite after I come home I simply press the remote control button and disconnect the battery.
The car resets itself and ALL of it's Computer Modules overnight and then the next day I can drive it with "Everything" functioning perfectly!
I did this the harder way of disconnect the Negative battery cable and strap down the Trunk...this is much easier..
As my Dad would say..."There's more than 1 way to skin a cat"

We ALL know that besides BMW's $329.00 Diagnostic Fee no matter what Module, Coding, Programming solution that they find ..the overall repair will quickly head to over $1,000.00 and solve the same thing that a $35.99 battery disconnect can do!

So again I ask you...
Rather than a $35.99 work around would you spend Thousands to BMW to repair the same thing on a 16 year old car?
Sometimes it just IS as it IS.

Then when I trade it in..Reset it overnight and even if they pull a scan the results will look good..
My mechanic told me..(before he replaced my valve cover gasket...)
If you are just going to sell or trade in your car...
"You never repair your car for the next guy!"

 

BudB,
My first car was a 1973 Oldsmobile Cutlass Supreme; station wagon! Haha. It met an unfortunate demise after a couple of years.
Good luck with the dealer; I'm naturally pessimistic but I hope they can diagnose the issue.
While I like the idea of the remote kill switch; do you think it can handle the loads for starting etc? Will it inadvertently cause any other issues?
I've been watching this guy Ivan on YouTube; Pine Hallow Auto Diagnostics. You really need someone like him to check it out. He's in State College, PA; so that might not help.
Good luck,
Fred

 

While I like the idea of the remote kill switch; do you think it can handle the loads for starting etc?

It's rated at 250 Amps.

Here is one that a guy put on a Hummer..rated at 180 Amps

It would be harder to convert to a Top Post Battery because it just has lugs to attach Crimp on Batter Cable leads

It seemed like a much easier solution than to actually Hardwire a mechanical Kill Switch into the car.
There are Kill switches that attach to the battery but then then I'm back to Strapping down the Trunk and stuffing a rag into the latch so the trunk won't fully close.

I'm actually tempted to do this first and save the $329.00 + at BMW.
The only thought about spending the $329.00 at BMW is in case the solution is really inexpensive...meaning around the cost of the Diagnostic to $600.00 to $700.00
I mean does anybody think that I'd get out of BMW for less than $1,000.00?

I'd like to do it proper but money is money.
If BMW comes back with a huge estimate to repair..then..
Add the Remote Kill switch to make my life easier and start looking for a new car to trade it in on and move on..
It just hurts that I just put 5K into the car which would have been for naught.
I imagine I could do the "Kill Switch" method for quite awhile.
Once the car is reset it really is a nice car to drive!
If I put up with all the idiosyncrasy's of the car up to losing the Power Steering's Power Assist which takes about a day and a half until the errors get that far it's still nice to drive..just nothing in the car works...LOL
C-R-A-Z-Y
I just wanted to repair a car to drive and then it loses it's mind!!
My car gets Dementia that I can reset and then a day later it gets it again LOL

I mean...Who makes a car like that...Well right now it's BMW!

 

I've been watching this guy Ivan on YouTube; Pine Hallow Auto Diagnostics. You really need someone like him to check it out.

I agree..
My BMW Independent Mechanic while he is Great on the Mechanical side of the car I know is scratching his head on my car and I think that the solution is a bit above him.
I do not know where that CanBus / Computer BMW Geek is.

I tend to think that with ALL that my car is doing how like a cancer the errors once started continue to Grow..
First the Alarm will not Arm but doors will lock then Steering Wheel and Cruise Control..next morning Power Windows cease to function and then Power Steering..
It is a gradual thing and not all lost at once...
Like the problem travels slowly down a chain of events.
And that someone that truly understands the "System" would know of the likely culprit(s) without even looking at it.

I told the BMW Service Writer that I cannot imagine that my BMW is the only BMW on the planet to have experienced this phenomenon and knowing the facts alone would offer a solution or at least where to look
He said, "Yes BMW Dealerships and BMW does communicate and from this Service Bulletins are created and maybe there is one that relates to what your car is Experiencing..
So let's get your car in for Service and we will get right on it!"

I said...I'll get back to you and took his card..

 

I just read back over some of the posts above. You'd mentioned that the car's battery voltage was only about 12.3 volts with the engine running. If so, the problem is almost certainly just a bad alternator. The BMW has a very sophisticated electrical system that selectively disables various electronic items when it senses inadequate electrical supply. you NEED (!!!) to measure the voltage with the car running - if it's not within a few tenths of a volt of 14 volts, you need a new alternator (or at least a voltage regulator - search on the two here).

Oh, and it would have been the same with your old Oldsmobile, too. ;-)

 

Thanks for your reply...
In post # 3 above I stated

UPDATE:
Checked Battery Voltages this morning after sitting overnight
Pre-Start: 12.34 Vdc
After Start: 13.94 Vdc

Does 13.94 Volts while car is running indicate a good Alternator?

 

I think 14 Volts is good, not likely an issue with the alternator.

 

Though it sure would have been nice if it was that simple of a fix...

 

I guess I misread the post on that subject - sorry for any false hope of an easy fix. ;-)

 

No Worries...It's all good in the neighborhood.

Made the appointment at BMW for 8 am on Wednesday.morning.
If nothing else it will just be nice to finally know exactly what's going on with the car!
Kinda like a puzzle solved.

 

UPDATE:Sorry for the length...
I got the estimate from BMW...took them almost a week which tomorrow will make.
* They want to "Start With" Replacing the Safety & Gateway Module (SGM-SIM) $2174.54 + $329.00 (Diagnostic Fee) plus taxes and shop fees. ($2503.00 plus)

The "Start With" is because they expect that there are more modules to replace but they need to replace the SGM-SIM first then do another "Diagnostic" to determine what else if anything needs to be replaced
The SGM-SIM is like exploratory surgery LOL

And they tell me that "I Really Need To" replace the "Oil Pan Gasket" for $2989.44 plus taxes & shop supplies.
They say this with a very straight face...
I told them that I add a quart of oil about every 4 to 5 months so a little over 2 quarts a year..
Yea I don't think I'll be spending over $3,000.00 to save me $20 bucks a year in oil!

I asked Wes the Service Writer would he spend 2500 dollars to just wait for another estimate that could be the same as the first or even more on a 16 year old car?
He said "No I would not"
I thanked them for their time but declined their estimate for repair.
So, it cost me $329.00 to get BMW's Repair Estimate.
I'm sure that there is a lesson there somewhere but I'm not quite sure I know what it is.
The lesson is probably..
To think that my car going into BMW would come out with a repair "Win" was probably "Very Optimistic" on my part! LOL
Though I don't think that's why I took the car to them..
I took it to them because I wanted BMW to tell me what the car needs to bring it home in regards to repairs.
I heard about the SGM...I did not have that info going in.

I priced the SGM-SIM at another BMW Dealership (their on-line offering was just over $400.00)
Provided I have the right Part #./ I'll get the part # while I'm at BMW picking my car up later this morning.
Used SGM-SIM's go for around $150.00 on eBay.
So I will go ahead and replace the SGM Via my BMW Mechanic
He charges $140.00 per Hour plus the SGM at $150.00 and I figure I can get the job done for around $300.00.
I can save just over $1800.00 which leaves me that amount in case there are more modules to replace.

BMW was not sure if the SGM would completely fix the issues hence the "Start With" to cover themselves.
If I'm lucky it will.
Then the BMW Diagnostic was not a total loss.

BUT

Going forward I'm still in the "Hindsight" is 20/20 stage of my cars repair(s)
What will the "Outcome" be if I put more $$$ into the cars repair.
Will I see a Light at the end of the Repair Tunnel and come out a Winner in this?
Or just spend more $$$ just to come up losing in the end and wasting $$ that I could have put down on another car.

I should have titled this thread..The Repair Hindsight of owning a BMW.
In the end do you "Win or Lose"

In my case I think about ALL that I have already done...

• Valve Cover Gasket ($700.00)
• Transmission / Mechtronics ($1300.00)
• Water Pump / Thermostat ($1100.00
• Oil Filter & Cooler Gaskets ($300.00)
• Air Conditioning ($1800.00)
• New Tires ($900.00)
• Tinted Windows "Ceramic" $400.00

Total $6500.00 and growing..

But at the same time...after all of the above...do I just walk away....
I really want to bring this restoration full circle and be done..Enjoy my hard work and $$$ spent
I started out on this because New & Used car prices are so high right now..
I thought...I'll Invest into the Nice Ride I already have..
Yes in "Hindsight" and if I knew then what I know NOW I would probably not have started down this road..
But I'm here NOW...back at the repair crossroads...
Do I cut and Run or keep going?
I know family & friends on the outside looking in will say...
What are you doing?
Stop putting $$$ into that car...
You need to let it go and get another car..
BUT
I can't help but think that with all that I've done to the car it is in great operating condition "Mechanically" for years to come...
Now I just have to fix it's Brain and it's done...
Decisions ...Decisions...

 

Gotta be frustrating... If it was my car (so I'd have the equipment I have) I'd disconnect the battery and get it working right, then do a scan with a BMW-specific tool to get any codes that exist. Then I'd re-scan the second the errors all came back, and see if those errors point to anything specific.

With the BMW bus-oriented systems, one funky module can "take out" a bunch of others - and worst case, it's intermittent. Maybe you'll still get the full laundry list of errors like the photos above. Or maybe it'll be a truncated list that gives you a hint as to the root cause.

Or not. These are tough ones!

 

Thanks for the reply.
It seems like a BMW's logic is like tentacles on an octopus..LOL

A bit of luck on my part...
Today I found the SMG-SIM Module Part# 65776975686 for $75.00 with a 1 Year Warranty. ( thank you to BMW for giving me the part #)
It came out of a 2004 BMW 645ci 2 door coupe that was hit in the back but Module working fine.
When it gets here my Independent BMW Tech will Install, Program & Code the module.
Then we will see what's next.
BMW said that might fix my problem or could lead to another module.
The other module mentioned both by BMW and my Mechanic is the SZL

Switch Unit Steering Column 613010

61319136898

I already have that ordered and waiting for pickup at a local BMW dealer in Miami.
Once the SMG-SIM is installed we'll see if I need the SZL or not.
Least expensive new part was $881.00

Keeping my fingers crossed that the SMG is all I need.
Though I usually don't get that Lucky!

FYI: Link to site that I found the SMG-SIM Part
Used OEM BMW Parts - Shop Online - AH Parts Dismantlers

 

UPDATE: (14 days after picking up my car from BMW)

I picked up my car from BMW on August 31st.
That night I Reset the car via disconnecting the Negative battery cable.
Next morning I connected the Battery and my car has operated perfectly ever since
Before my car's visit to BMW the longest it lasted without noticeable errors was 1 day.
I'm now on day 14.

I have since received the SMG Module and figure I have 2 choices.
1) Replace the SMG Module even though the car is not experiencing any errors
2) Wait until the car goes into it's run of errors and then replace the SMG module.

I figure that #2 operates on the principle of "If it ain't broke don't fix it"
Though to think that my car will never experience what it had in the past is "Wishful Thinking" and it's just a matter of time.
At this point I will not drive with the windows down or Sunroof open for fear that at any point the errors could pop up and I would not be able to close them without a 4 hour battery reset.
With rainy Florida days popping up at any time that would not be a good scenario.
I am leaning towards #1 and just replace the SMG module.
Face the problem head on.
Though...
In my 25 years experience repairing X-Ray Equipment it would probably surprise you how many times just unplugging a connector, cleaning the contacts and plugging it back in will fix the problem.
Some X-Ray rooms have been installed for 20 years or more and over time contacts can oxidase.
I will often try this first in a KISS method "Keep It Simple Stupid" before spending hours running down a solution.

My thoughts are if BMW unplugged the SMG Module in my car and then plugged it back in that alone could have repaired the 16 year old contacts and account for the "No Errors" in my car.
Or it's just plain coincidence that after BMW looked at my car it is running error free for 2 weeks...Or 14x better than before it went in.

So...what do you think?