My 2002 sl500 had been making a creaking noise, usually accompanied by a blue ABC warning light. When I had the problem diagnosed, the dealership said the ABC pump needed to be replaced. After the repair, the blue light persisted but the car drove fine. Recently though, the creaking has returned and is more frequent and the ABC light that comes on is red and says 'drive carefully.' Any ideas on what this could be?

 

Its possible that now to pump has completely failed and is not putting out any pressure at all. I dont think this relates to a creeking noise. Maybe you need ball joints too.