Certainly! There are a few common issues that might cause the cruise control on your 2000 Jeep Grand Cherokee Limited 4.6L V8 Quadra-Drive to stop working. Here are some steps to diagnose and potentially fix the problem:

1. **Check the Fuse:**
- The cruise control system has a dedicated fuse. Locate the fuse box, which is usually under the dashboard or in the engine bay, and find the cruise control fuse using the diagram on the fuse box cover. Check if the fuse is blown and replace it if necessary.

2. **Brake Pedal Switch:**
- The cruise control is designed to deactivate when the brake pedal is pressed. A faulty or misaligned brake light switch can cause the cruise control to disengage. Locate the switch near the top of the brake pedal arm and ensure it is properly aligned and that the electrical connections are secure.

3. **Clutch Pedal Position Switch (if manual transmission):**
- Similar to the brake pedal switch, the clutch pedal switch ensures the cruise control disengages when the clutch is pressed. Verify its condition and alignment.

4. **Vacuum Leaks:**
- The cruise control system relies on a vacuum to control the throttle. Inspect the vacuum lines for any cracks, disconnects, or leaks. Pay special attention to the line connecting the cruise control actuator to the intake manifold.

5. **Throttle Cable:**
- The cruise control cable may need inspection. Check for any signs of wear, fraying, or disconnection in the throttle cable.

6. **Speed Sensor:**
- The vehicle speed sensor (VSS) sends speed information to the cruise control system. A malfunctioning VSS can cause erratic cruise control behavior or prevent it from engaging. The VSS is typically located on the transmission. Inspect the wiring and connection to ensure there are no issues.

7. **Cruise Control Module/Actuator:**
- If there is no fault in the switches, fuses, or sensors, then the cruise control module or actuator could be at fault. These components are more complex, and while you can inspect them for visible damage or loose connectors, testing or replacement may require specialized tools or further diagnosis.

8. **Electrical Connectors and Wiring:**
- Ensure all connectors related to the cruise control system are secure. Look for any loose wires, corrosion, or damaged connectors in the harnesses.

9. **On-Board Diagnostics (OBD-II):**
- Use an OBD-II scanner to check for any stored fault codes. Even if the check engine light is not on, there may be codes that can help pinpoint the issue.

Here's a basic process you can follow:
1. Start with the simplest checks like the fuse and brake/clutch pedal switches.
2. Move on to inspecting vacuum lines and the throttle cable.
3. Check the speed sensor and electrical connectors.
4. If all else fails, consider the cruise control module/actuator.

If you've performed these checks and still cannot identify the problem, detailed diagnostic and repair work beyond typical DIY methods might be needed. In that case, consulting a professional automotive technician could ensure a precise and safe resolution to the problem (even though you mentioned that asking a professional is not an option).

These suggestions should give you a good place to start troubleshooting your cruise control issue.