Remove toothed belt - see operation "Toothed Belt, Remove and Install".
Remove fastening bolts from toothed belt tension roller (3) and detach tension spring (1). Remove toothed belt tension roller with bracket (2).
Install, Connect
Insert toothed belt tension roller (2) with bracket. Install fastening bolts for toothed belt tension roller (3) and tighten slightly. Insert tension spring (1).
Install toothed belt - see operation "Toothed Belt, Remove and Install".
Remove, Disconnect 
Install, Connect 