Ignition Light Problem - 1977 350SL - Ignition light never c

[badshead]

The other day I accidently shorted across 2 terminals in the engine bay by dropping some wire wool on them. I discovered that one of them is live even with the ignition off. The non-insulated terminals are connected to what appear to be 'Bosch' resistors or similar (located on passenger side of  engine bay near diagnostic connector). At first the ignition light faintly glowed when turning ignition on, prior to starting, but is now permanently off whenever the ignition is switched on. Car starts and runs OK and all other dash instruments work fine. Have I trashed the alternator or some other component? If so what's the best way of checking?  I'm not entirely sure that the 'shorting' is the cause as the car has been laid up over the winter and I'm not sure if all was well before.

 

[Andy]

Ignition Light Problem - 1977 350SL

Hi Bill

Before getting in to deep. Check the alternator wires are secure at the rear & not broken. Then remove the alternator regulator held in with two screws and check the bushes are not worn out.

Regards

Andy @ www.mercedesservicing.com

 

[badshead]

Ignition Light Problem - 1977 350SL

Thanks Andy - I'll get the spanners out and let y know how I get on.

 

[badshead]

Ignition Light Problem - 1977 350SL

I tested the voltage at the battery terminal with the engine off and then again running at 2000 rpm - result was the same voltage so not looking too good for the alternator! I've removed the brushes which have approx 8mm left on each - what should they be? It looks like they are removed by melting solder at the base and therefore easy to change? Does anybody know where I can get replacement brushes?