lost electrical charge on 85 300sd
 

While driving to work this morning, I noticed my radio went out, then the windows would not go up at the normal speed. I pulled over to inspect the alt belts, and they are in good shape as should be the alternator since I replaced it about 1 year ago.

I parked it, and it would then not start at all. The batt is dead.

I was wondering if this could be related to the fact that while waiting on some gears for my odometer, I have been driving the car without the instruments connected, not one of them. Do they have to be plugged in to make the car charge?

Also, I inspected the regulator, and the brushes are in good shape.

Any ideas? Thanks.

You could try charging the battery to see, if it will take a charge. Other than that you're going to have get it started to do much more diagnosis. You could either have a short in your battery/charging system or simply a bad alternator. Once you get it started you can check the alternator output with a voltmeter and go from there. I can't see that having your instruments disconnected would do anything other than keep you clueless on vital engine data (temp, oil pressure, charging system, fuel, etc.).

Personally, I would park my car before driving it routinely with no instruments.

Good luck.

Re: lost electrical charge on 85 300sd
 

I've had the same problem - while driving the lights would dim, radio would quit work as well as all instruments. The battery was fully discharged. The reason for all that was that one of the brushes in dynamo broke. The dynamo did not charge the battery and after some use the battery was dead. With engine running and no electric power it must be the dynamo - you don't actually need a battery when the engine is running.

I think your problem is your dynamo doesn't produce any voltage. Install a fresh battery, start the engine, use a simple voltmeter on battery terminals and rev up the engine - if there is no increase in voltage the dynamo (or voltage regulator located on the dynamo) is bad and needs to be repaired.

Dynamo meaning the alternator?

Yes. Should have used alternator. Dynamo is an old expression. Although alternators produce AC and dynamos DC the original name for them all was a dynamo.