I need the location of a control module.

Unless someone here has exact info, you might be better served searching for VW Jetta forums. Specific vehicle forums are usually owners sharing their experiences, repairs, tips, wiring and diagrams as a free source without resorting to dealer or repair shops. There's no guarantee of an answer but you're more likely to find help from VW Jetta owners. There are also service manual info, sometimes free when searching online or subscribing to alldata.diy or Mitchell data for online access to service manuals.