it stops on high? odd. bearings would be my guess... as in high, the resistor pack is out of the circuit. your fuse is the original or the upgraded strip fuse on the fender? 91 should be on the fender, and the 30 amp strip fuse may be cracked... pull it and look it over carefully.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!