STLBMZ1 install on SLK R171: Why does the green AND red LED blink after installing the module?

Question:

Why are both green and red LEDs blinking after installing the SmartTOP module on a SLK R171?

Answer:

The red LED indicates that the module is connected to the incorrect plug. In this particular case it is important to know that the SLK has two CAN bus distribution blocks right adjacent to each other and both are linked together with a very short wire pair that is usually brown and brown/black or brown/grey. The objective during installation is to find the correct plug that leads directly to the top control module. If the module is accidentally connected to the aforementioned interconnect instead of the top control plug,  the module would work but other control units like parking sensors etc would also be affected. 

It is very important to find the correct plug with a pair of brown and brown/red wires to connect the module to.

If you get both blinking green and red LEDs, simply try all the can plugs on the OTHER CAN block as described in the manual.