Yes, absolutely talk to peter@gdl-online.com......he is a real good guy. He rebuilt my amp and the thing now works great...easy to take out and re-install. it is the silver box with electric harness connected located under drivers side dash to the left of steering wheel column. Your actuator may need work also (located in engine compartment, with linkage connected to it). the 95% most likely fix is to rebuild the amp as these things ALL fail....I would be willing to bet that more than 9 out of 10 123 diesels need work on the amp.

good luck