kurtis104

Hello All,

I recently had some electrical gremlins in my 2005 E320 CDI with 200k miles. I ended up trying to find it with an amp meter and pulling fuses and so on. I did find some interesting things but not sure I found "IT". So I installed 2 new batteries, and put the fuses all back in place and now have perhaps a new problem. (Previously My battery was going dead if the car was not driven every day).

My keys (both of them) no longer seem to be recognized in the ignition so I can not turn the key. Strangely the key will lock/unlock the car and so on but not turn to position 1 or attempt to start the car.

Needless to say, I have checked and rechecked most all of the fuses that I had out (checked for placement and for continuity) and they all check out good.

I also have no activity in the instrument cluster (though perhaps this is because the key is not recognized. The steering column lock does not make any unlock noise. There is lots of other activity and noise under the hood (brakes pumping up, fuel pumps coming on, etc.)

Strangely, the radio will turn on with things in this state.

What I cannot find is definitive wiring diagram and dependent fuses for the EIS or ignition switch.

Also does the battery control module control or activate this? I have replaced it with another used part from ebay.

Any thoughts from the more experienced out there? I am a capable DIYer but tend to need some basic resources like a wiring diagram or other type of info.

Thanks in advance.

kurtis104

The good news is the battery does not drain in a
day
Guess I will have to check the eis connector for power?

so the EIS recognizes that a key is
present and has power. Guess I will be
off to dealer to reprogram. I also might stop replying to myself here - lol.

if anyone has any sort of experience here your thoughts. ?

Terri

Hey Kurtis, slightly different problem in that my car has been sitting for about a year now. Unfortunately, both batteries went flat during this time and after doing some work on the car, we've discovered that the key won't turn it on anymore. Both batteries are fully charged now, but both were taken out of the car and slowly charged on a battery tender. Now it turns everything on but won't turn the ignition . . . what did you do to fix your car (assuming you were able to)?

kurtis104

my problem was a loose cable in the trunk. There are 4 behind the battery that distribute power to rest of car. I had them each off while trouble shooting my current leak. One was “on” and tight but not tight enough. In my case key gob locked/unlocked door but nothing else as no power ,

assuming new key fob battery -and you have the right key. I had my EIS tested at ECU pro (nearby) and once it checked out good I found my bad connection problem.

We have 3 identical old E-Class MB and you would be surprised how many times we try the wrong key in a car

Good luck

Terri

Thanks Kurtis, food for thought. We have friends who are Mercedes techs and they're stumped. I'm thinking it's probably a similar problem as that would make the most sense. I have to laugh at your three . . . I have a love/hate relationship with my one . . .