Engine Stalls When AC Is Turned On
 

1995 E300. When I depress the buttons that provide AC, the engine shuts down immediately unless I am at speed. When at speed the AC compressor does not operate though. While I haven't been able to check if the compressor is locked up I thought I'd see what other things may come into play. Thanks!

Mine would do this before I replaced the wiring harness, has yours been replaced with teh updated harness?

IIRC the idle speed is computer controlled (one of the very few things) on the 95 E300 and an eco wiring harness issue can cause oddities.

I also installed a new OVP at the same time for good measure.

At idle, when you engage the ac, watching it, does the belt lock for any time? I'm not sure on a 95 even if anything electrical could kill the motor... It's gotta be the compressor locked.

Unplug the clutch and it likely won't stall.

Plan for ac rebuild....

I've seen this same thing happen when the a/c compressor was locked up.