[MTUser]

Hello,

I found a really nice (exterior/interior) 99 S420 that I would like to buy (I have a beater 99 S420 that could be a parts car). The owner states that it is parked because one day the key would not turn in the lock when he stopped to do an errand. The key can be removed from the lock.

I've tried to read as much as I can about this issue, and watch YouTube videos. It seems it is sometimes possible to fix this problem by buying a new key from Mercedes. If that doesn't work, is the only option getting the car towed to dealer? I was wondering if you found a good mobile mechanic that worked on Mercedes you could get this done at the seller's residence?

My concern is my understanding from watching videos and reading is that if you cannot turn the key to the #1 position, there is no easy/simple way to remove and replace the ignition mechanism. Has anyone here done this job when you cannot turn the key?

Anything else I should be asking the seller or thinking about? All advice/suggestions/comments gratefully received.

 

[MAVA]

On these 98/99 cars, can be finicky as it can be a transponder/key problem,but.................... A climate system fan drawing too much current can cause it. BAD WIRING-yes bad wiring(bad temperature probe sensor too) in the Climate air plenum in the engine bay.

The plenum has like four or five large Philips Screws. A) unplug the Fan controller B) The Temperature probe plugs on the bottom of the plenum about 1/3 the distance from the fan. just unplug the electrical connector, and inspect the two to three wiring there on the connector-Sorry I have no pictures of it.

martin

 

[MTUser]

On these 98/99 cars, can be finicky as it can be a transponder/key problem,but.................... A climate system fan drawing too much current can cause it. BAD WIRING-yes bad wiring(bad temperature probe sensor too) in the Climate air plenum in the engine bay.

The plenum has like four or five large Philips Screws. A) unplug the Fan controller B) The Temperature probe plugs on the bottom of the plenum about 1/3 the distance from the fan. just unplug the electrical connector, and inspect the two to three wiring there on the connector-Sorry I have no pictures of it.

martin

Thank you Martin. I think I know what you mean. My S420 (not the one I want to purchase) had a howling like a helicopter taking off and landing when I bought it. From researching here, it was suggested it was a bad bearing in the fan in that container. So I remember disconnecting the fan control unit on top of it, and replacing the fan with one I purchased on eBay. No more howling.

Am I correctly seeing in my mind what you describe above? I think I can certainly try that first. It would be an easy fix in the seller's parking lot.