Solution to early W163 8-key limit

[ladfalat]

Brief History: 1998 ML320, daughter ran battery down, upon recharge, crank but no start. After new ignition switch (electrical), fuel filter and pump, determined through process of elimination that key, ring antenna module, or AAM is fried. Ordered new mickey mouse key (valet), car fired right up, no trip to the dealer for any programming; the mickey works right out of the box, if your ring antenna and AAM are sound. Right now it is the only key I have that convinces DAS to allow a start. I do have two remotes/folding keys that work but the DAS chips appear to be fried.

So, I go and order one more mickey. MBUSA tells me that the one I just received is the 8th, and there ain't no more, even if I stomp and roll on the ground. So, putting the dash and stuff back together THE SOLUTION hit me.

SOLUTION: I detached the ring antenna from the cylinder lock, taped Mickey through the ring hole to the ring, wrapped it all in bubble wrap and squirled it away under the instrument panel. You got several inches of wiring. You see where I'm going. Until Mickey gives up his electronic chip soul, any of my DAS-dead keys will start the car, because Mickey is always in the hole. Both my dead keys give me a DAS LED authorization flash when turned, BECAUSE MICKEY IS ALWAYS IN THE HOLE, safely hidden away. So proud of myself, but then again, I can't be that brilliant, so why have I not read this.

Now, even if I lose both of the DAS-dead keys (FOBs with working remotes), I can always get the replacement blade from MBUSA, and mate it to any dummy FOB, at least to unlock driver's door and drive home.

What am I missing here?

On related topics, electrical portion of ignition switch can be replaced by taking off only bottom panel under steering wheel and the trim around the steering wheel itself. A pain but doable, instrument panel does not need to come out, just the surrounding trim. But if you have gone that far, replace burned out bulbs.

[ladfalat]

OK, why didn't that work, not so brilliant after all. Next morning, no authorization with the fried keys. So, pull off triangular panel to the right of the steering wheel, fish out the ring antenna with the valet key attached, take the key away, put it back into the ring antenna, turn the fried key to position 1, LED now authorizes, truck starts. Hmmmmmm!!!!!!!!!! Does the ring antenna need to see movement in the key occasionally, or does it need to see separation. I thought that when there is no key in the ignition, the AAM and ring antenna modules are "OFF". Have to find that post on another forum where someone got a hold of new 7930 chips, and found a way to program them. Any leads?

So, back to ring around the lock cylinder, valet key in use, till I figure this out.

[97 SL320]

Have a look at the " Directed Electronics " web site, they make remote car starters and key chip foolers. The tech section might give you some hints as to operation.

From you description, it sounds like the key is an actual pin and tumbler type Vs the electronic ignition switch used on later cars. If so, it should have a DAS X system ( not to be confused with the DAS Xentry diagnostic tester )

I've run DAS X with a key stuck the the antenna when testing a ECM and DAS box and had no problems.

[hihosilver]

I usually leave the key in the car when its in the garage but when I shut it off I pull the key out and put it right back in to reset it if that helps