The modulator valve is part of the transmission system. On most Chrysler vehicles with automatic transmissions, it's typically located on or near the transmission itself. However, it can be difficult to access without some mechanical knowledge and potentially requiring removal of some other parts.
To find it, you'll need:
1. Your specific Chrysler model and year: This is crucial.
2. A repair manual: A Haynes or Chilton manual for your specific vehicle will have diagrams and detailed instructions showing the location of the modulator valve and other transmission components. Online repair manuals are also available, but be cautious of their accuracy.
3. Caution: Working on the transmission system is complex and can be dangerous. If you're not comfortable with auto repair, it's best to have a qualified mechanic perform any work.
Without knowing the exact Chrysler model, I cannot provide a more precise location.