Electrical issue - C240

[mslc791]

This morning about 20 minutes after start my '01 C240 displayed this message: Undervoltage Consumer Defective!. The fault than clears when the car is started and again reappears some 15-25 minutes later. I also noted a noise coming from the passenger side of the engine when I start the car in the morning. Chirping short (and intermittent) noise, reminds me of the noise that waterpump bearing makes when busted. Has someone experienced something similar. Is this type of alternator serviceable like old ones were - I mean regarding replacement of voltage regulator? I could not locate voltage regulator for this model.

Thank you.