Tracing a short to ground can be a complex and time-consuming process, but here are some steps you can follow to help diagnose and locate the short in your Mitsubishi Challenger:

1. Safety First: Before starting any electrical troubleshooting, ensure that the vehicle is turned off, the ignition key is removed, and the battery is disconnected to avoid any potential electrical hazards.

2. Visual Inspection: Inspect the wiring harness, connectors, and components for any visible damage, loose connections, or burned/melted insulation. Look for any signs of frayed wires, exposed conductors, or signs of overheating.

3. Disconnect Components: Start by disconnecting one component at a time that is associated with the circuit where the short is suspected. This can be done by consulting a wiring diagram specific to your Mitsubishi Challenger to identify the components connected to the circuit.

4. Fuse Testing: Check all the fuses that are connected to the circuit where the short is suspected. Use a multimeter to measure the resistance across each fuse or visually inspect them for any signs of blown fuse elements.

5. Using a Multimeter: Set your multimeter to the continuity or resistance mode (Ohms). Attach one multimeter lead to the positive terminal of the battery and the other lead to the wire or component being tested. If the multimeter reads zero resistance or beeps, it indicates a short circuit to ground.

6. Trial and Error Method: If the previous steps did not uncover the short, you may need to employ a trial and error method. This involves systematically disconnecting specific sections of the wiring harness or individual wires of the circuit until the short is eliminated. This process can be time-consuming but is effective in locating the short.

7. Pinpointing the Short: Once you have narrowed down the area or component where the short is likely occurring, you can further investigate by inspecting the specific wiring, connectors, and related components within that area. Look for any signs of abrasion, pinched wires, loose connections, or damaged insulation.

8. Repairing the Short: Once the short to ground has been located, repair or replace the affected component, wire, connector, or fuse. Make sure the repairs are done properly, following manufacturer guidelines or using professional-grade repair tools if available.

Remember, troubleshooting electrical issues can be challenging and time-consuming. If you are unable to locate or fix the short yourself, it is recommended to seek professional assistance from a qualified automotive electrician or mechanic.