We have two of these Stairlifts, bought used at different times, and both of them only had the upper positive line brush. In both cases the brushes were hanging out on their springs – and they are certainly vulnerable to damage on re-installation. For the first one I figured that the other brush had been lost, so I manufactured a replacement. The second lift is working fine without the second brush – it doesn’t give a “2” error code. So I’m not sure whether they _are_ required? I suspect that …
Update – from the Simplicity Quick Reference Guide, the lower brush would be for the optional Slide Track – so it’s not required for a regular installation. Indeed it might even create a short-circuit / some other problem. So I guess that the charging circuit _is_ made through some other metal-to-metal contact. Kinda weird ….
