I have a 98 ml ,got it at auction,battery needed to be jumped,started no problem,we drove for 5 hrs,no charged on battery,so we replaced it,now it turns but wont start(run for a second or 2).Anyone have any ideas?
Thanks

Sounds like your ML has lost the programming on at least one ignition key. If you have a second key try that. MB told me it couldn't happen, but I think when the battery is jumped, strange things happen to the AAM. That is the All Activity Module which is programmed to accept up to 8 keys, but only two at a time. If the key has lost it's programming, you can get it to crank by switching it real quick from off to the starting position. Then The AAM locks out the starter after 2 seconds if it doesn't recognized the key.

If you turn the key slowly to the start position, pausing at least two seconds in the on position, does it crank at all? Does the little security led below the 4WD switch blink slowly, or not at all?

You cannot fix this on your own unless you buy one of the programmers that MB uses, currently about $700. Some EBay sellers claim they have a laptop version up for bid, but be very carefull if the seller has no history or ratings.

You can try to have the MB reprogram the AAM using the existing keys. Figure 1/2 to 1 hour shop time and they may try to sell you a new AAM and/or new keys.

Type in AAM in the search program at the top for more info.

Good luck! (BTDT)

Jim in Phoenix

Actually, you can have more than 2 keys active at once. You can actually have all 8 keys active at the same time. Of course dealer can deactivate specific keys any time.

Definitely sounds like your having problems with the security/authorization system. Definitely try another key, if the problem persists then it may be anything from the antenna to the computer.