SIR Wire Repair

Figure 36:

Figure 37:

The Supplemental Inflatable Restraint (SIR) system requires special wiring repair procedures due to the sensitive nature of the circuitry. These specific procedures and instructions must be followed when working with SIR system wiring, and wiring components (such as connectors and terminals).

Tool Required:
J 38125-A Terminal Repair Kit

If any wire except the pigtail is damaged, repair the wire by splicing in a new section of wire of the same gauge size (0.5, 0.8, 1.0, etc.). Use the sealed splices and splice crimping tool from J 38125-A Terminal Repair Kit for these repairs. Use the following wiring repair procedures to ensure the integrity of the sealed splice.
1. Open the harness by removing the tape.
^ To avoid wire insulation damage use a sewing "seam ripper" (available from sewing supply stores) to cut open the harness.
^ Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
^ Do not use the crimp and sealed splice sleeve to form a splice with more than two wires coming together.

2. Cut the wire.
^ Cut as little wire off the harness as possible. You may need the extra length of wire to change the location of a splice.
^ Adjust splice locations so that each splice is at least 40 mm (1.5 inches) away from other splices, harness branches, or connectors.

NOTICE: Follow these procedures in the order listed. If the wire strands are damaged, repeat the procedure until a clean strip with all wire strands intact is obtained.

3. Strip the insulation.
^ When adding a length of wire to the existing harness, be certain to use the same size wire as the original wire.
^ To find the correct wire size do one of the following:
^ Find the wire on the schematic and convert the metric size to the equivalent AWG size.
^ Use an AWG wire gauge.
^ If you are unsure of the wire size, begin with the largest opening in the wire stripper and work down until achieving a clean strip of the insulation.

4. Strip approximately 7.5 mm (0.313 inch) of insulation from each wire to be spliced.
^ Be careful to avoid nicking or cutting any of the strands. Check the stripped wire for nicks or cut strands.
^ If the wire is damaged, repeat step four after removing the damaged section.

5. Select the splice sleeve.
^ Select the proper sealed splice sleeve according to wire size.
^ The splice sleeves and tool nests are color coded (see the following chart).

6. Use J 38125-A Splice Crimp Tool (Figure 36) to position the splice sleeve in the proper color nest of the hand crimp tool.
^ Place the splice sleeve in the nest so that the crimp falls midway between the end of the barrel and the stop.
^ The sleeve has a stop (3) in the middle of the barrel (2) to prevent the wire (1) from going further (Figure 37).

7. Close the hand crimper handles slightly to hold the splice sleeve firmly in the proper nest.

8. Insert the wire into the splice sleeve until it hits the barrel stop and close the handles of the crimp tool tightly until the crimper handles open when released (Figure 37).
^ The crimper handles will not open until the proper amount of pressure is applied to the splice sleeve.

9. Repeat steps 6, 7 and 8 for the opposite end of the splice.

10. Using the heat torch, apply heat where the barrel is crimped.

11. Gradually move the heat barrel to the open end of the tubing.
^ The tubing will shrink completely as the heat is moved along the insulation.
^ A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is achieved (Figure 37).