'99 Clk320

[Lucas1]

I'm trying to find a DTC description and diagnostic steps for B1421. I'm currently in school and am taking an auto climate control class. We have to do a presentation, as a part of our final, on an Auto HVAC sytem and I chose this car since my mother-in-law has one. The information available on Shopkey and Alldata, which we have at school, is VERY limited. I can't even find what sets the DTC or what the symptoms would be. It looks like it has something to do with the condenser fans, but I can't find what.

If anyone could help me out, it would be great. I need to know: 1. A description of the DTC, 2. Conditions for setting the code, 3. Steps to diagnosing the code, and 4. Possible repairs needed to fix the car.

Thank you