EAM,AAM,NOW THIS!!!! ML320 died
 

my ml320 died 3 weeks ago, literally died. its still in the shop and after replacing the extended activity module, and the all activity module the thing still won't start! ($800+$800+6x$140/hr!!!). now they tell me they need 3 or 4 more days and have to replace the engine's cpu and if that fixes it they may be able to put back the original eam and aam. guy says he's never seen this before. 2002 ml320 bought with 95k and dealer maintained (the dealer that hias it now). are these guys screwing with me or did i just buy a lemon? looking at 4k + and a month with no car to get it back!! i will be driving it to the next lot and trading in for a domestic ride. any advice????? please help!:mad:

givin the nickname of alabama trash can I've read in places it's no surprise. but if you bought it from a dealer you may have some recourse. if not your up S- Creek without a paddle

On a 2002 ML320, the AAM & EAM have NO influence on starting OR running!

Did they give you any idea of codes from the truck? IS there a DAS issue?

DAS is controlled by a module (FBM) that plugs into the EAM.

DAS= drivers authorization system (anti-theft)

dogbolz, sounds like you need to find some MB dealer techs who are trained to diagnose problems with your vintage MB automobile. Unfortunately for many techs if their high tech diagnostic equipment can't pinpoint the problem for them the resolution is a struggle, and you pay for their on-the-job training.

Sounds like they are guessing, not diagnosing. Lazy way of fixing is to throw parts at until they get lucky/you go broke. Fire their lazy arses!

no i did not get any codes from them. interesting first point i will bring that up with them. thanks.

You were diving down the road and the engine shut off and wouldn't re-start??? Or maybe you turn the key and nothing happens??? Some details would be helpful.

$140/hr from non MB mechanics?? My MB indie (master tech) is much less than that. It sounds like they are throwing parts at it

"Alabama trashcan" now that's funny. I hate working on those things. Figure chrysler left 2 points off the star, intentionaly.

no, its at an MB dealership, MB techs working on the car.

yes driving down the road and the dash lit up like an xmas tree so i pulled over, engine still running. tried to take off and gears would not change (stayed in first). turned car off with fingers crossed and that was it. no turning over, dead as a doornail.......

here is what they sent, see attached.

By that print-out... looks like either a CAN issue (connections behind the cluster) OR

that the ME fuel system computer is to blame.

They should be able to unplug that computer & see if the other computers can exchange info.

I was waiting to see what the wizened ones had to say. IMHO it could be any of a number of modules on the CAN which is "bringing down the CAN". Could also be CAN wiring, but the most common fault is a module on the CAN itself, even the overhead control module. I'd even say "especially" the overhead control module, aka the trip computer, we had a number of those fail back in the day, I do remember one failing and causng a problem like this, and the tech rep said to start with trying to disconnect the trip compter, then see if the active CAN codes went away, which they did.
The tech rep did say if disconnecting the trip computer didn't solve the issue, then plug it back in and proceed to the other modules on the CAN and do the same thing, disconnect, check for active CAN codes, plug back in if they were still there, proceed to another one, etc until the one that was shorting out the CAN was found. So this is whay I recommend, again starting with the trip computer Overhead control panel or OCP.

What MBDOC is saying makes sense too and much easier to access the sfi computer, there is some trim work involved in disconnecting the trip computer, but man we used to replace those things left and right back in the day. You might even see if there is any campaign/warranty work relating to this truck yet, there were so many campaigns on the trip computer on 163's I've lost track!

The first ECU queried in the short-test is VG, or the transfer case ECU. The exclamation point to the right is telling us that SDS can't communicate with it!!! Also, most of the CAN codes are CURRENT, which means the problem is happening NOW!!! A simple CAN voltage test is the first thing that needs to be done. With the key ON, the CAN H should be around 2.6 volts and CAN L around 2.4. If not, the VG should be disconnected (it's under the center console to the rear of the shifter), and the voltage re-checked. I'd also look very closely at the wires going to the transfer case motor. I won't go into too much detail. The dealer guys should already know this, or at least one of them should.

This isn't really that complicated a diagnosis. There must be more to the story though. The short-test is quite clear as far as I'm concerned.

I agree it is quite clear the CAN has crashed and they probably shouldn't be throwing these parts at it until it's certain why the CAN is down.

They have no idea what they are doing.

BTW:

Both CANH and CANL should be at 2.5 volts when not active, but can be up to 0.9 volts apart from each other.

CANH active should be between 2.75 and 4.5 volts.
CANL active should be between 0.5 and 2.25 volts.