How to Replace the Wiring Harness in a 1987 Yugo GV

Introduction

Replacing the wiring harness in a 1987 Yugo GV can be a daunting task, but with some preparation and patience, it is quite doable for a mechanically inclined owner. The wiring harness sends power and ground to all the electrical components in the vehicle, so replacing it will restore functionality if your harness is damaged or corroded. In this guide, I will walk through the complete process of replacing the wiring harness in a 1987 Yugo GV.

Reasons for Replacement

There are a few main reasons why you may need to replace the wiring harness in your 1987 Yugo GV:

Electrical shorts/opens: If wires are damaged or corroded, it can cause electrical shorts or open circuits that prevent components from working properly. Replacing the harness will restore connectivity.
Rodent damage: Rodents love to chew on wiring harnesses, which can sever connections. A new harness will be needed for repairs.
Upgrading the system: You may want to upgrade to a more modern harness to support new electronics like audio systems. The old harness may not have enough wires or circuits.
Restoration project: When restoring a 1987 Yugo GV, replacing the 30+ year old harness is wise to ensure everything works properly and to prevent future electrical gremlins.

Preparation

Replacing the wiring harness is not a small undertaking, so proper preparation is key:

Review harness diagrams: Obtain the wiring diagrams for your Yugo and become familiar with all the connections. This will help during removal and installation.
Label wires: Before removing the old harness, use small tags or tape to label both ends of each wire so you know where they connect.
Purchase replacement harness: Source a new complete harness designed for your make/model. Custom harnesses can also be built.
Gather tools: Necessary tools include screw drivers, wrenches, wire cutters/strippers, electrical tape, and crimp connectors. Have them ready to go.
Allocate time: Plan to spend 5-10 hours over a weekend to replace the entire harness. Rushing increases the chance of mistakes.

Removal of Old Harness

With the prep work complete, it's time to remove the old wiring harness:

Disconnect the battery: Always disconnect the battery ground cable before working on electrical systems.
Remove interior trim: Take out all necessary trim pieces to access the harness routing.
Unplug connectors: One by one, gently unplug all the wire connectors throughout the car, using your labels as a guide.
Cut cable ties: Cut any zip ties or fasteners securing the harness. New ties will be used for the replacement.
Pull from conduits: Carefully pull the harness out of any rubber grommets or conduits. Temporarily remove them if needed.
Coil and remove: Once fully disconnected, coil the harness and pull it completely out of the vehicle.

Installation of New Harness

Installation is essentially the reverse of removal:

Route new wires: Referring to harness diagrams, route the new harness through the same conduits and openings as the old one.
Secure with ties: Use zip ties to secure the new harness in place, preventing sagging and interference.
Insert connectors: Following your wire labels, plug all the connectors back into their respective components. Triple check connections.
Insulate ends: Properly insulate any unused or open wire ends so they don't short. Tape works well.
Reinstall trim: Put all interior trim pieces back in place to complete the harness installation.
Reconnect battery: Reconnect battery ground cable once the job is finished.
Test operation: Start the engine and turn equipment on to verify proper operation. Check for any shorts or faults.

Conclusion

While replacing the wiring harness in a 1987 Yugo GV is a time consuming job, it is definitely doable for a DIYer with mechanical skills. Proper labeling, harness diagrams, patience, and care when removing and installing will help ensure success. Take all necessary safety precautions when working with electrical systems. Replacing the old brittle harness will restore reliability to your Yugo's electrical components.