The carriage has a weak point, the peg that supposed to keep the belt clamped into the carriage tends to snap off during normal operations. If you're getting error code 86:01 and Carriage slipping on belt, you don't have to buy a whole new Carriage! This clip mode is designed to retain the belt even more securely than the original HP design.
This clip is compatible with the following Carriage Designjet Assembles: CQ305–60016, CH538-67018, CH538-67044
You can just buy this part or book an engineer to repair and service printer at the same time.