Everything is normal when my '93 240 is running. But when the car is off and the key is removed the battery light comes on.
I have replaced the diode plate and regulator to no avail.

Hope you guys can help, you have never let me down.

Matt from Pittsburgh

Usually, that's a sign that one or more diodes in the alternator are shot. Check the wiring on the back of the alternator to make sure everything is intact, including the ground. If you can get a boneyard alternator for cheap, try plugging that in to isolate the problem.

I have already replaced all the diodes, brush, and regulator. If anyone has any ideas I would greatly appreciate it.

Matt

I know you're looking for fresh advice, but don't overlook the possibility that the diode set you installed was faulty. Again, about the only readon for the dash light to come on when the ignition is shut off and the key is out is bad diodes. You might consider pulling the alternator and taking it to an auto electric shop to have it checked.

I am definitely not overlooking the problem. In fact we checked all the old diodes that were removed and all check good. I just don't have any other ideas on what could be happening.

Thanks again,

Matt

OK, that's odd but never say never... I would next get a wiring diagram and check the leads going to the alternator (for continuity, and for integrity of insulation), and also the battery cables - especially the ground. Also, the ignition switch itself may have developed a problem - have you tried switching it on and off rapidly several times (without engaging the starter)?