Group,
I want to test or run a speedometer on a workbench. I am not trying to calibrate or test any thing other than the fact that the speedometer drive operates and the odometer gearing is in tack. I can assume that the speedo drive is powered by a signal that originates at the tail shaft sensor but I can't find what the end electrical product is at the speedometer. Would it be possible to use a signal generator and stimulate the drive in the speedometer to turn? If so dose any one have specific knowledge about what frequency and shape the signal should be and what voltage and current involved? Also is a primary power source required at what connections? I know repair shops bench test these units. I have several of these 126 chassis VDO units that need tested and I feel there is a way but need help to get started. These speedos are all from the 126 and 107 Mercedes (alike)
Thanks Bruce Buchanan,