After the unsuccessful attempt in repairing the K40 module assembly I decided to replace the complete assembly. Even though the solder connections were solid the actual relays may be defective when in use. I located a used module from a donor 1999 SLK230 that had gotten into a front end wreck. I removed the original and installed the replacement module. I also went ahead and soldered the known area of solder connection problems.

The car has been running strong for approximately 700 miles with no CEL activation. I can conclude the 2nd K40 module is working properly.

The auto dim mirror has always been stuck at the 3/4 mark of the mirror. I checked out the new and used prices and they were way out there! The new mirrors were close to $400 and the used mirrors from dismantlers were around ranging in the $200-250 range. I don’t need the “auto” dim feature”, I can manually flip the mode with no problem. I actually prefer to get the manual version so I won’t have possibility of this happening again in the future. Especially with a used replacement.

I picked a manual version up and replaced mine with no problems at all. The mirror I was able to get did have a few cracks on the plastic housing but fixable with the use of 2-part epoxy.