Battery light remaining illuminated when key Is off and removed.

[Meta6981]

Background: About three weeks ago I stopped to put some fuel into my car (1981 300sd om617) when I hopped back in and drove home (around the corner). When I got back home I killed the engine and alas the battery light was lit up. I was in a hurry and had another place to be, so I popped the hood and disconnected the battery. The next day when I went to start it up again The glow plug light was not illuminating and it had a hard start.

Since this i have replaced the voltage regulator, I have replaced the plug that connects to the back of the alternator. Also When the alternator is not connected the glow plugs function normally.

I also noticed that when the key is off and the key is pulled out I noticed that the gauges are not shutting off as well, This was a more recent observation and is making me think the ignition switch might not be working correctly. The Tumbler was replaced last year by a local private benz shop.

Since this i have been disconnecting the battery at every stop more than about 2 hours and have been charging it with plug in charger every night.

Any Idea's on what you may think the problem is? Or how to check the ignition switch and or replace it?

 

[The Warden]

You mentioned that the gauges are not shutting off when you remove the key...do the gauges act normally when you disconnect the alternator, or do they still remain on with the key off?

It could be an internal short in the alternator...a short, especially on an M-B, can backfeed electricity in VERY strange ways, particularly in the instrument cluster.

If the gauges continue to misbehave even with the alternator unplugged, you might take a look at the key switch...I remember us talking about that being a possible concern; did you ever have a chance to get any info about whether the key switch can be adjusted?