Sorry for this presumed dumn question, but I am new to this forum (and to Corvette) Great car. What is DBS, MN6?

 

As of now, it cannot....

 

Anything can be defeated. There must be a pin which makes the column actually lock. How about removing the pin or blocking the hole that it locks into?

Or turning the hole into a slot if some sort of contact has to be made? A slot which would allow the pin to pass through on either side would easily defeat any "locking pin" mechanism.

 

Once the BCM is reprogrammed not to send the signal to the SCL during shutdown, SCL would be a moot issue. GM only included the steering column lock because it was Federally mandated and that law expired in time for the MY06-07 to be SCL free. I don't think GM can remove 05 SCL's on a retroactive basis, but I would think some 3rd party could figure it out.

Would DBS go away if SCL went away? I suspect not because the car still would require reverse to be engaged to shut the car down. However, this too, could be reprogrammed.

 

I had the column lock problem on my 2005 C6 Z51 at 2200 miles. It took the dealer nearly two weeks to get the part. I feel your pain.

 

DBS = Dead Battery Syndrome; MN6 = manual 6speed.

Also I believe blocking the lock mechanism itself will do nothing -- electronically -- as there's a relay that sends info to the BMC, locked or not. You would have to completely defeat (rewire?) the system.

 

DBS refers to the situation we ran into last year with excessive dead batteries in '05 MN6 cars *despite being properly shut down in reverse*.
Roughly 1/4 of all MN6 poll respondents in dead battery polls had this, whereas A4's had only a 5-6% dead battery rate. DBS or 'dead battery syndrome' was the term created by vote on this forum to separate out the problem from dead batteries with A4, and from owner errors or other explainable dead batteries. Because the reverse and column lock requirements have been removed from '06, (may be related to DBS) it may well be that DBS is gone, but final proof of that is not yet known. The '06 MN6 dead battery rate is much lower than '05, but maybe not low enough to be entirely certain:

http://forums.corvetteforum.com/poll...pollid=1500606

 

Well took my 2005 C6 vert Z-51 MN6 out Friday night and put it away. Went on a one day trip came back this morning and went to get in to the C6 and the battery is dead. I checked the locking column and it was not locked. If anyone else gets a DBS can you please check to see if you can move the steering wheel. My thought is there is a problem in the program of the computer that does not shut down because it does not detect the steering wheel locked and causes the battery to go dead. I have taking the car to the dealer once and they can not find any problem.

 

The column lock has nothing to do with DBS. It's been shown time and again. I left my column unlocked all December as an experiment without incident.
However, experience has shown that if you take more time and deliberation in exiting your car, there is less chance of DBS. Take your time and manually lock your wheel each time before you get out of your car. I have had no DBS in over a year doing just this.

 

I have been very careful to make sure that I lock the column. I have not had it happen sense until this morning. I have let the car sit for up to 6 weeks and it starts right up. I was in shock when the battery was dead this morning so quick and when I checked the steering wheel it was not in the locked position. The last thing I normally do now is to make sure that I can not turn the steering wheel. Guess I blew this Friday night. I have read other people post that said it is not the locking column but the last two time my battery was dead the wheel was not locked.

 

Do you remember rushing your exits for some reason?
There have been rare reported column lock failures producing frequent dead batteries, so a dealer check may be in order.
DBS, when it happens, drains the battery just as if you forgot to shut down in reverse. So the car will be dead the next or following morning, depending on your battery's state of charge. If you can see those little biddy blinking red lights in your car after day #2, you good to go then for at least weeks.

 

It took my dealer almost 2 weeks to get the part to fix the coumn lock. Hopefully will not have to go through this again.

 

I don't think SCL has been ruled out, nor does "locking" or "unlocking" the SCL have anything to do with DBS. DBS, correctly stated is a drained battery of undetermined cause and its' charge is below the 12.2 volts required to start the car. SCL is fires the second you punch the ignition switch to the off position; the lock pin is released and is now ready to engage the locking hole(s) in the lock ring at any time thereafter. SCL doesn't care if you are in reverse or whether the locking pin is in the locking hole

Why do I think DBS is caused by SCL? Simple, if the SCL malfunctions, in any way, and there are several, proper shut down of the computer system is prevented and anything down stream from SCL that requires a computer signal to shut down never receives the power down command. Unless the SCL reports an error, the computer system will never record an error code because, technically, there is no error-just nothing down stream is shutting down, draining the battery. The last computer controlled item to turn off(if that's the right word) that I know of is the transceiver which is waiting to see if there is the correct FOB present and whether you took the FOB with you.

Why do I think DBS is not caused by forgetting to shift in to reverse. Simple, shut down the car in any gear state but reverse and see what happens. In my car, bells go off, and the DIC has a "Shift to Reverse" message; all of which are very hard to ignore-if you do then you earned your fate. Perhaps more importantly, that DBS has all but gone away with 06's.

I think an interesting idea would be to do a VIN study of repeated DBS cars with focus on equipment and date of manufacture.

 

Excellent break down. I guess I meant to say that locking the column or not has nothing to do with DBS.
It's possible that the SCL can malfunction, irrespective of it being locked or not?

 

What I used to see, after a DBS/No start, was very high charging (14.5~14.9)rates being reported to the DIC even after recharging the battery. This held true until the entire SCL system was replaced. This morning my charging rate was 14.1~14.3 with A/C on as well as headlights on, moving from stop light to stop light.

With SCL locking, the final act is that the pin is extended and the pin is available for engaging the locking ring. SCL doesn't care if the pin actually enters the hole, its' done once the pin is fully extended and "touching" the locking ring. If SCL module detects a problem & doesn't "crash" right away it will throw an error code, the computer system gets that message and prevents the car from restarting-the car, however, is fully shut down and the battery charge appears okay. Some codes can be cleared by removing the negative ground from the battery, but a full blown error is a call for the hook because that car is not going anywhere-that behavior is a design safety feature. If SCL is a diagnosed issue, from comments on this forum, a complete replacement of the entire SCL system for a successful halting of DBS and SCL events is required.

DBS is maddening in trying to diagnose the cause because it doesn't happened every time. That said, DBS is the result of something not going into its' "off" state and has a fair amount of draw. This draw is not the engine, lights, stereo, A/C, Cooling Fan, OnStar, or fuel system; all that is left that I can think of is the SCL, the transceiver, and elements of the Computer System. Just from comments on this forum, DBS seems to begin most often after washing the car on an incline sligth or otherwise.

 

If I read you right, your SCL was defective and has been replaced. And your DBS is now gone?

You are aware of the underhood light deal with the inclines?

I never wash my car, yet had 3 or 4 episodes of DBS...
And I never park on any inclines...

 

Yup, with the replacement of all the SCL system & three batteries later, DBS went away now for just over a year.

Yea, I looked at that light and even had disconnected the light for several months, but to no avail. If you rap on the Right side hood strut it will blink off and on.

The only reason I mentioned the washing bit was that when my DBS started and that several members have stated a similar onset. I washed my car in my drive which has a 8% incline; when I finished I got in to the car to pull in to the garage, but nogo/no start. I checked the battery and it was somewhat low-way more than it should have been all things considered. Anyway, I hit with the charger and the car started later. I took it to the dealer the next day, but only got the usual "blame the victim treatment" that only a dealer can give. At first DBS would hit once a month, then once every two weeks, then about every 7 days, and finally, every other day. Only about midway did SCL start showing up in error codes, but never occurred the whole 45 days the dealer had the car. Even when they clearly had fixed the SCL & DBS, I was blamed with creating the problem in some mystic manner.

 

I would suggest that since SCL failure has been only rarely reported on this forum, that you're particular DBS problem or reason for DBS may not be the usual.
But it surely may give clues as to the cause(s).

 

Perhaps, however, given the absence of any other found cause and because of the profound reduction in DBS in MY06-07 cars with SCL removed, my money is with SCL or problems stemming from SCL. Nevertheless, the real shame of all this is GM and Delphi are no longer actively looking for a solution and they are leaving the problem up to the dealer techs' to sort it out. If you are a good Tshooter you may find what is happening, but my advice to anyone with chronic DBS is to get a deep cycle battery that can take DBS abuse-Ciao!

 

You're obviously into the electo-mechanical details more than I.
My view is mostly anecdotal and non-technical.

I'm sure you're aware of my proposal about a defective reverse sensor causing DBS, stemming from the fact that my DBS prone car can get the DIC warning 'shift to reverse' despite being shutdown in reverse.
Today I got an email about another DBS prone '05 MN6 with this same characteristic.

Could it be that the SCL is upstream of the reverse sensor in the shutdown process, and may actually be the part that is hanging up, delayed or defective, and not the sensor itself?