Gilly, power seat(s) question: I've read about the power seats
 

inoperable when the key is not in the ignition. My 2003 ML350 still behaves this way. Would you suggest bringing it in to have that activated? which means dropping it off, a 2 week service appointment with a good luck on the loaner....or is the retrofit/fix something a capable DIY can do? Thanks in advance for your help.

Tom:
I know what you're talking about. I think the seats "time out" after awhile. Try turning the key to on, then off, and see if the seats work then. I believe they will. I don't think it's programmable on the later ones like this, after 2000 or so. It was the actually wiring that was changed. On the earlier ones it was a programming change, but it's illegal for us to activate it, because if you activate the seats to work with the key off, the power windows would also work key off, which is against the law in the US. BUT I do believe there was a modification we could/can do to have it legal. There is very little on these that a DIY'er can do in regards to programming changes. Some things are up to the owner to activate, such as the automatic locking.

Gilly

Yes
 

...you are right, the power seats do "time out" after a while. But the key must be inserted in the keylock position 2 in order for the power seats to activate.

However, I want to operate the power seats even without putting in the key in the keylock, or, after using my key fob to "unlock" the vehicle.


Gilly -- see this link at the very bottom (service bulletin #TSIMBNA9133) -- it is a MB TSB, i'm sure you're familiar with it already. BUT, is this the fix for my problem???? Whats your $0.02?

Thanks for any input.

Tom:
No, that doesn't apply to your truck. The AAM was redesigned in 2002, and actually I think this was all fixed by 2000 in production vehicles. The DTB you linked to relates to the 98s and 99s. There is a wiring change that would allow the seats to legally operate with the key off.
I had time later in the day to reacquaint myself with what I was trying to remember from past experience with the 2002 and newer trucks.
What the 2002 intro book states is this:

Convenience control
-If the ignition/start switch is moved from the On to the Off position and the front doors remain closed, the convenience control (power windows, sliding/lamella roof, seat adjustment, exterior mirror adjustment, interior lights) is active for 30 minutes. If one of the front doors is opened, the duration of the convenience control of 30 minutes is restarted. On US models, only the seat adjustment is still active after one of the two front doors is closed.

What I discovered today (or rediscovered I guess), is that if you leave the door OPEN for a half hour, the interior lights will shut off and the seats no longer work. I then closed the door, and the interior lights came on. I should have checked at that point if the seats would work, but I didn't. I am almost 100% sure that if the lights were "on" that the seats would have operated. I reopened the door right away instead, and the seats did operate.

If you are sure that the seats are inop immediately after shutting off the engine, I would say there is a problem with the programming in this truck. Maybe you can go to the dealer and ask them to look at it. Show the what it's doing wrong, and also possibly you can ask them to compare it with a different 2003, like on the showroom, and they can figure it out. Hopefully it's just the version coding in the AAM. Are the dome lamps working normally?

Gilly

Thanks for the additional updated tech info about the pwr seats Gilly
 

I will check this convenience control feature when I get home today.

CORRECT! My 03 works the exactly the same way

Hmmmm, that would make sense since. I would have to check mine too.
I reopened the door right away instead, and the seats did operate.

Now that you mentioned the 30-minute interval, IIRC (not sure yet) my power seats still operate.

I'm sorry...still quite a bit ignorant with MB/ML speak but what is "AAM"? what does it stand for?

Dome lamps work perfectly.

The AAM is the All-Activity Module. Other manufacturers would probably use the term "BCM", the Body Control Module.
It buried in the front fuse box. It controls many of the body functions of the truck, such as door locks, lights, alarm, wipers, the list could go on and on. It can be accessed using the shop computer (SDS) and the version coding checked for the various functions. Possibly something is set wrong. But check what I've mentioned about possibly the seats are just "timing out". If the interior lights are operating, the seats should adjust. If you notice the interior lights aren't coming on and the seats aren't operating, and you just opened the door, there is something wrong, possibly a door switch isn't working.

Gilly

Gilly: answers
 

As long as the overhead lights are on (which indicates one of the front door is open) the power seats will remain on even without the key in the ignition.

As soon as you the overhead lights are off, the power seats are off too.

My findings on a 03 ML500:
 

Went out to truck.
Open door, seat will work.
Get in truck, close door, key not in ignition, seats don't work.
Turn ignition on, seat works.
Turn ignition off, remove key, seat works (and I assume will work for 1/2 hour).
Open door, seat works (and again I assume will work for 1/2 hour).
Close door (I stayed in truck), seats don't work again.

Gilly