Crimp Barrels, Heat Shrink, and Wires

Use the table below to determine the appropriate crimp barrel and heat shrink tube to use when performing the repairs described in this procedure.

The terminal replacement kit contains replacement terminals and wires. All wires are yellow to make sure that any subsequent diagnostic work enables a technician to see that there was an earlier repair done on the terminal.

Repair Guidelines

Repairing damaged electrical harnesses can save significant time and material costs compared to replacement. Every repair can affect reliability, so it is important to match factory-level quality. Follow the procedures and best practices described in this document to have a correct repair.

If the repair cannot be completed to factory-level quality, the harness must be replaced.

Wires marked with a single + marking in the circuit diagram indicate a safety-critical circuit (Figure 6). A single + marking on the pin name in the circuit diagram indicates positive power (Figure 7).

If a connector needs to be replaced or more than 1 wire in a harness needs to be repaired, plan the locations of the repairs and mark each wire with the approximate location of the splice. Avoid placing the splices next to each other to minimize the increase in harness diameter. Stagger the splices as much as possible (Figure 8).

Tesla Technicians should document the repair of any electrical connector. Instructions for documenting are included in the internal supplement document.

Repair Using a Single Splice

Using a single splice to repair a wire shortens the length of the wire segment. A wire can be repaired with a single splice in the following circumstances (if any of these do not apply, refer to the “Repair Using a Double Splice” section of this document instead):

• The damage is to 1 wire in 1 location.
• The length of the damage is less than 10 mm.
• The harness is long and loose enough to be unaffected by the shortening caused by this repair.
• The repair will not put excess strain on the wire where it enters the connector or harness transition (Figure 9).
• Not applicable for CAN repairs. CAN wires must be the same length on CAN H and CAN L.

1. Disconnect all of the necessary electrical connectors to electrically isolate the harness from the vehicle, or disconnect 12V power.
2. Use a multimeter to check for voltage on the circuit being repaired.
   Warning

   Do not perform this procedure while the circuit is energized.
3. Make sure that there is enough room to work comfortably on the circuit being repaired. Protect all surfaces that can be damaged by heat in later steps.
4. Tesla technicians: Photograph the damaged area. This photo will be uploaded to the Toolbox session (see internal supplement document). Describe the original routing of the wire and the location of any harness coverings, tape, or conduit.
5. Refer to the circuit diagram to find the correct wire size.
6. Refer to the “Crimp Barrels, Heat Shrink, and Wires” section of this document to find the proper crimp barrel and heat shrink tube for the size of the wire.
7. Cut out the damaged portion of the wire.
   CAUTION

   If more than 1 wire in the harness needs to be repaired, cut only 1 wire at a time to eliminate the risk of joining the wrong circuits.
   Note

   If the damaged portion is over 10 mm, refer to the “Repair Using a Double Splice” section of this document instead.
8. Slide the heat shrink tube over one end of the wire.
   CAUTION

   Do not skip this step. The procedure will have to be repeated if the wire is joined without installing the heat shrink tube.
9. Hold the wire near the cut area while stripping the end of the wire so that there is enough exposed conductor to reach the center stop of the crimp barrel (Figure 10). Repeat for the other end of the wire.
   CAUTION

   Do not hold the harness by a connector when stripping the wire. This can damage the crimped terminals inside the connector.

   

10. Inspect the wires for damaged or missing strands.
    • If strands are damaged and the wire still has sufficient slack, cut the wire again and repeat step 9 using a larger diameter setting on the stripping pliers.
    • If strands are damaged and the repair will shorten the wire enough to put strain on the wire where it enters the connector or harness transition, perform the procedure in the “Repair Using a Double Splice” section of this document, using a larger diameter setting on the stripping pliers.
11. Inspect the wires for oxidation and corrosion.
    Note

    If brown or blue-green oxidation is present on the copper strands, cut out the entire section of oxidized wire, and then perform the procedure in the “Repair Using a Double Splice” section of this document.
12. Confirm that the routing of the wire matches the original configuration.
13. Insert the crimp barrel into the proper channel of the crimp tool and squeeze the handle lightly to hold the barrel in place. The impression of the crimp should be centered on the seam of the barrel (Figure 11).

    

14. Insert the exposed copper wire into the barrel. Make sure that the wire is fully inserted, no strands extend from the side of the barrel, and no insulation is present inside the barrel.
15. Fully squeeze the handle to crimp the barrel. The crimp tool releases only when the barrel is fully crimped (Figure 12).

    

16. Repeat steps 13–15 on the other side of the barrel.
17. Apply tension to the wires and make sure that the crimp holds securely. If the wires come out of the barrel, do not attempt to re-insert them. Cut the wires, remove the barrel, and refer to the “Repair Using a Double Splice” section of this document.
18. Move the heat shrink tube at least 60 mm away from the joint to prevent it from shrinking during soldering.
19. Put on cut-resistant mechanic’s gloves or other heat-resistant gloves.
20. Protect all surfaces that can be damaged by heat from the soldering iron.
    Warning

    Always read and understand the soldering iron operator’s manual before using it to solder or shrink heat shrink tubing.
    CAUTION

    Do not use the soldering iron in an area where surrounding surfaces, materials, or components could be damaged by hot air.
21. Solder the connection:
    1. Make sure that the barrel and wire are free of dirt and grease.
    2. Install the soldering tip on the soldering iron.
    3. Allow the soldering iron to fully warm up.
    4. Clean the tip of the soldering iron on a damp sponge.
       Note

       Replace the tip if it does not have a shiny appearance, or if solder does not melt on the tip when it is fully warmed up.
    5. Apply a small amount of solder to the tip of the soldering iron.
    6. Use the soldering iron to apply heat to the center of the barrel for a few seconds (Figure 13), then apply solder into the center window (Figure 14).

       

       

    7. Stop applying solder when it fills the inner opening of the center window (Figure 15).

       

    8. Remove the soldering iron from the barrel before the solder wicks into the wire insulation or the soldering iron overheats the insulation.
22. Hold the joint still while returning the soldering iron to a safe location.
23. Turn off the soldering iron and allow it to cool.
    Note

    Heating the soldering iron unnecessarily degrades the surface of the soldering tip.
24. Inspect the solder joint. If the solder is in a spherical shape, or did not evenly flow across the crimp window, the soldering iron was not hot enough (Figure 16). Repeat from step 21.

    

25. Slide the heat shrink tube over the barrel, aligning the center of the heat shrink tube with the center of the barrel.
26. Once the soldering tip has cooled, remove it from the soldering iron and install the flame tip and deflector tip.
    Warning

    Make sure that the soldering tip has cooled completely before removing it.
27. Use the soldering iron to affix the heat shrink tube to the wire (Figure 17).
    CAUTION

    Continuously move the soldering iron to avoid overheating any specific section of the heat shrink tube or wiring. Any discoloration of the wiring insulation indicates overheating.

    

28. Turn off the soldering iron and return it to a safe location.
29. Allow the heat shrink tube and wire to cool.
30. Inspect the heat shrink tube to make sure that it is fully sealed to the wire and that the adhesive is bonded to the wire insulation.
31. Tesla technicians: Photograph the repair. These photos will be uploaded to the Toolbox session later (see internal supplement document).
32. Hold the repaired area against the rest of the harness, then wrap the harness with the electrical tape that is supplied with the wire harness repair kit. Apply tape to 50 mm of the harness on each side of the splice (Figure 18).

    

33. Re-apply any harness coverings, tape, or conduit that was in place prior to the repair (Figure 19). Apply new harness tape, if necessary.
    Note

    If the repaired wire is routed incorrectly, do not leave it as-is. Cut the wire and repeat this procedure to restore the wire to the way it was routed from the factory.

    

34. Tesla technicians: Upload the “before” and “after” photographs of the repair to the Toolbox session (see internal supplement document).
35. If the damage was caused by the harness contacting another part of the vehicle, make sure that the harness is adequately supported or restrained to prevent future damage.

Repair Using a Double Splice

1. Disconnect all of the necessary electrical connectors to electrically isolate the harness from the vehicle, or disconnect 12V power.
2. Use a multimeter to check for voltage on the circuit being repaired.
   Warning

   Do not perform this procedure while the circuit is energized.
3. Make sure that there is enough room to work comfortably on the circuit being repaired. Protect all surfaces that can be damaged by heat in later steps.
4. Tesla technicians: Photograph the damaged area. Describe the original routing of the wire.
5. Refer to the circuit diagram to find the correct wire size.
6. Refer to the “Crimp Barrels, Heat Shrink, and Wires” section of this document to find the proper crimp barrel and heat shrink tube for the size of the wire.
7. Cut the wire to remove the damaged portion. Minimize the amount of wire removed (Figure 20).

   

8. Cut a section of new wire that is at least 100 mm longer than the damaged portion. This ensures that there is adequate slack when the second end of the wire is spliced.
9. Slide the heat shrink tube over one end of the wire.
   CAUTION

   Do not skip this step. The procedure will have to be repeated if the wire is joined before installing the heat shrink tube.
10. Complete the first splice, following the procedure in the “Repair Using a Single Splice” section of this document (Figure 21).

    

11. Cut the repair section to the required length (Figure 22).
    CAUTION

    Leave enough length to properly insert the stripped ends into the crimp barrel. Wires that are too short put excess strain on the wire where it enters the connector or harness transition.

    

12. Slide the heat shrink tube over one end of the wire.
    CAUTION

    Do not skip this step. The procedure will have to be repeated if the wire is joined without installing the heat shrink tube.
13. Complete the second splice, following the procedure in the “Repair Using a Single Splice” section of this document.

Repair a Terminal

Take care when repairing a single terminal. It is advisable to practice removing the retainers or locking clips on scrap connectors before performing the repair. Practicing greatly improves the success rate for removing a terminal without damaging any additional components.

1. Disconnect all of the necessary electrical connectors to electrically isolate the harness from the vehicle, or disconnect 12V power.
2. Use a multimeter to check for voltage on the circuit being repaired.
   Warning

   Do not perform this procedure while the circuit is energized.
3. Make sure that there is enough room to work comfortably on the circuit being repaired. Protect all surfaces that can be damaged by heat in later steps.
4. Tesla technicians: Photograph the damaged area. This photo will be uploaded to the Toolbox session (see internal supplement document).
5. Release the retainer or locking clip that attaches the terminal to the connector housing.
   Note

   Some connectors have retainers and others have locking clips.
6. Use a terminal back-out tool to release the terminal clip that attaches the terminal to the connector housing.
7. Cut the damaged terminal off of the wiring harness. Make sure that there is enough wire remaining on the wiring harness to do a single splice.
   Note

   Make sure that the cuts are straight and clean (Figure 23).

   

8. Slide the heat shrink tube over the end of the harness wire.
   CAUTION

   Do not skip this step. The procedure will have to be repeated if the wire is joined without installing the heat shrink tube.
9. Remove insulation from the harness wire and terminal pigtail. Make sure not to remove too much insulation (Figure 24).
   CAUTION

   Be careful not to damage the copper strands.

   

10. Complete the terminal pigtail splice, following the procedure in the “Repair Using a Single Splice” section of this document.
11. Insert the new terminal into the connector housing. Make sure that the new terminal is firmly secured.
12. Insert the connector locking device and reconnect the connector to the vehicle.
13. Perform a functional test of the newly repaired circuit.

Replace a Coaxial Cable

Coaxial cables are not repairable. However, some individual coaxial cables are available separately. Disconnect the original cable and route the new cable along the existing harness. TN-20-17-001, “Coaxial Cable Overlay Guidelines” provides instruction and best practices to replace a coaxial cable.

Make sure to follow these rules when installing a replacement coaxial cable:

• Wrap the new coaxial cable with harness tape before installation.
• Use cable ties or tape to attach the new coaxial cable to the harness bundle every 150–200 mm.
• Avoid sharp edges while routing the new coaxial cable. Apply edge clips, cable ties, or tape to the main harness as necessary to prevent the coaxial cable from contacting abrasive surfaces or edges of parts.
• If the damage to the original coaxial cable was caused by the coaxial cable contacting another part of the vehicle, make sure that the new coaxial cable is adequately supported or restrained to prevent future damage.
• Do not pull the new coaxial cable around corners or parts. The bend radius of the cable must be greater than 15 mm.
• Do not use sharp objects to pull the new coaxial cable through a grommet.
• Make sure that all grommets are fully sealed before reinstalling the parts that were removed for access.
• When installing a new coaxial cable that connects to a B-pillar camera, apply 150–200 mm of corrugated tubing to the end of the cable that connects to the camera, then wrap the corrugated tubing with harness tape.

Collision Repair-Specific Information