I have a 1998 ML320. Recently, when I withdraw the key the car "beeps" as though the key were still in the ignition and I cannot use the fob to lock the car (have to do it manually). After a lot of research - I think it is the ignition switch is faulty - apparently it senses the key in the ignition and that sensor can go bad. Some alternate suggestions were made in a previous post.

ML320 Remove Key & Column Lock Doesn't Occur

I would like to replace the ignition switch - is this difficult? How would I do it - do I need to disassemble the whole steering column to get it or is there a trick to pulling out the whole ignition cylinder, tumbler and switch as a unit so I can replace the switch. If I need to take apart the column - is this difficult?

Unrelated (I think) my ETS light has gone on. I think this must be the brake stop lamp switch.

A story on my 1999 ML 430 as a warning. A few years back (when still under certified extended warranty, thank god), my truck went "nuts" and when you turned the key off and removed it, not only did the car think the key was in the ignition, but the truck kept running. Then ALL the warning lights went on and stayed on. The only way to shut it off was to disconnect the coils. It was repaired through a total electrical box replacement, including all fuse panels.

Your situation has a few eerie similarities to what happened to me way back when. Just letting you know. I hope your truck does not have the same problem, as if so, it is $$$$.

Does the steering wheel lock? Can you here the bolt snapping into place as you remove the key? It may be binding and the aux switch built into the lock is not being activated. or the aux switch is defective or dirty. In the older Benzes you had to remove the instrument cluster to get to the lock assy. If the lock is binding, get some graphite lube and spray it thoroughly into the key slot. Wiggleing the steering wheel may help the lube work it;s way into the bolt area.

Good luck,

Jim in Phoenix

Interesting...is the steering wheel lock the click I normally hear and feel in the key when the key is removed, or is that a switch or lock or relay of somekind built into the lock assembly? I wish I had a diagram of the lock assembly, I could figure it out quick then I bet. I will try what you suggest.

I had a similar problem. The key has a sort of lock mechanism that clicks when you remove the key. Problem is with age the tumbler gets dirty and the mecahnism just doesnt click. So when the key is removed the engine thinks key is still in. I pulled out the key and had limited results. After cleaning the tumbler and springs when i remove the key i still have to jiggle the plastic ring around the key tumbler to engage thec "click" mechanism. i"ll try to post pics of the disassembled tumbler.