I've had Quartz movements where either the piece of plastic that insulates the negative battery contact has shifted and is blocking a solid contact, or where the metal strip that makes up the negative contact is pressed too flat to make a solid contact. Bending it gently upward has remedied that.
The good news, if all else fails, is that a new movement is only about $15 (but hopefully it doesn't come to that)!
Duncan very kindly took a look at the Sawtooth and tried a new battery but movement was dead so He very kindly ordered the updated replacement for the 7N36 calibre and will fit that in I will ofcourse post photos once its back with Me and a huge thank you to Duncan.
Okay its ready the Outstanding craftsman who has worked his magic has sent Me photos but I am currently in San Francisco on flying duties and what with the 8-hour time difference i'll ask if I can use the photos to show the marvellous work He has very kindly done.