Thanks Paul,

I gave it a quick parking lot inspection and the belt tension looks okay. I replaced the belt a few thousand miles ago. The compressor pulley is turning, but the clutch is not engaged.

Can someone walk me through the procedure for jumping the high side pressure switch and / or the thermostatic switch? Where are they located?

Of course I'll check for voltage at the compressor first to rule out the clutch coil. I'll also try your trick of disconnecting / reconnecting the battery. I don't have a pulse counter. Is that the same is the DIY "code reader tool" that has been described in old posts? Please elaborate.

Thanks again!

__________________
D.H.

04 ML500
02 E430

Experience is something you don't get until just after you need it.