Thanks for the replies Torriem, Headmech and 325mag. Thank you Torriem for telling me where to start to trouble shoot. The linkages and mechanisms under the white indicator seemed to be ceased from rust so I disassemble the works and lubricated and everything moves freely and easily now. I replaced the potentiometer also. In diagnostics the voltage does change as I lower and raise the header now. Good idea, Headmech I will attempt the calibration sequence with the header running tomorrow. 325mag the header does pause just above the ground and sometimes about 2/3 the way up. This a 2009 model with software 21.x that doesn't have the header calibration option. Thanks again for the helpful advice everybody