Why doesn't a 2000 Jeep Cherokee's overdrive work?

The overdrive in a 2000 Jeep Cherokee may not work due to several potential issues. Common causes include a malfunctioning transmission control module, low Transmission Fluid levels, or a faulty overdrive solenoid. Additionally, issues with the vehicle's electrical system or wiring could prevent the overdrive from engaging. It's advisable to have a professional diagnose the problem for an accurate assessment.