I'm working on the blower for my 300D (W124). Not sure where to go next.

Installed new blower, tested OK before install, now nothing. Fuse is good. This is the second blower in 6 months - installed a used one previously, now this one.

Where should I look next? The push button unit works as I get A/C and heat, and control deflection, etc. Just no blower unless I'm going 40 mph, etc.

Any help appreciated, thanks.

Doug