How to change an idler pulley on Isuzu Ascender 2005?

To change the idler pulley on a 2005 Isuzu Ascender, start by disconnecting the negative battery cable for safety. Remove the serpentine belt by using a wrench to relieve tension on the tensioner pulley. Next, unbolt the old idler pulley from its mount, then replace it with the new pulley, ensuring it is securely fastened. Finally, re-route the serpentine belt over the new pulley and reconnect the battery cable.