GM Service Manual Online
For 1990-2009 cars only

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

Terminal Repair Kit J 38125-A

Important: Do not use the terminals in the kit in order to replace damaged SRS terminals unless specifically indicated by the terminal package.

Essential tool kit J-38125 Terminal Repair Kit contains the following items:

    • Special sealed splices to repair the SRS wiring
    • Wire stripping tool
    • Special crimping tool
    • Heat torch
    • Instruction manual

The two critical features of the sealed splices are:

    • A special heat shrink sleeve environmentally seals the splice. Inside the heat shrink sleeve is a sealing adhesive.
    • A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low energy circuits.

The J-38125 Terminal Repair Kit also serves as a generic terminal repair kit. The kit contains the following:

    • A large sampling of common electrical terminals.
    • The correct tools to attach the terminals to wires.
    • The correct tools to remove the terminals from connectors.

SRS Connector (Plastic Body and Terminal Metal Pin) Repair

Repair damaged Supplemental Restraint System (SRS) wire harness connectors and terminals (except pigtails) using the connector repair assembly packs. These kits include an instruction sheet and the sealed splices. Use the sealed splices to splice the new wires, connector, and terminals to the harness. The splice crimping tool is color keyed to match the splices from J-38125 Terminal Repair Kit. You must use the splice crimping tool to apply these splices.

The terminals in the SRS are made of a special metal. This special metal provides the necessary contact integrity for the sensitive, low energy circuits. These terminals are only available in the connector repair assembly packs. Do not substitute any other terminals for those in the assembly packs.

If individual terminals are damaged on the sensing and diagnostic module (SDM) harness connector, you must replace the SDM harness connector using one of the following two components:

    • SDM harness connector pigtail assembly.
    • SDM harness connector replacement kit.

If individual terminals are damaged on any other SRS connection, the entire connection should be replaced. Use the appropriate connector repair assembly pack. You should replace the entire SRS wiring harness, if necessary to maintain SRS circuit integrity.

SRS Wire Pigtail Repair

Important:  Do not make wire, connector, or terminal repairs on components with wire pigtails.

A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail is damaged, the entire component (with pigtail) must be replaced. The supplemental restraint steering wheel module coil is an example of a pigtail component.

SRS Wire Repair

Tools Required

J-38125 Terminal Repair Kit.

Important: Refer to Wiring Repairs in Wiring Systems in order to determine the correct wire size for the circuit you are repairing. You must obtain this information in order to ensure circuit integrity.

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 mm, 0.8 mm, 1.0 mm etc.). Use the sealed splices and splice crimping tool from the J-38125 Terminal Repair Kit. Use the following wiring repair procedures to ensure the integrity of the sealed splice.

Important: You must perform the following procedures in the listed order. Repeat the procedure if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.

  1. Open the Harness.
  2. • Open the harness by removing any 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.
  3. Cut the Wire.
  4. • 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 in) away from the other splices, harness branches, or connectors.
  5. Strip the Insulation.
  6. • 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.
    • Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
    • Be careful to avoid nicking or cutting any of the strands. Inspect the stripped wire for nicks or cut strands.
    • If the wire is damaged, repeat this procedure after removing the damaged section.
  7. Select and Position the Splice Sleeve.
  8. • Select the proper sealed splice sleeve according to wire size.
    • See the following table for color coding of the splice sleeves, and the crimp tool nests.

    Object Number: 68642  Size: SH
    • Use the Splice Crimp Tool from J-38125 Terminal Repair Kit to position the splice sleeve in the proper color nest of the Splice Crimp Tool.

    Object Number: 68639  Size: SH
    • 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. Close the hand crimper handles slightly to hold the splice sleeve firmly in the proper nest.

    Object Number: 9502  Size: SH
  9. Insert Wires Into Splice Sleeve and Crimp.
  10. • Insert the wire into the splice sleeve barrel until the wire hits the barrel stop.
    • Close the handles of the crimp tool tightly until the crimper handles open when released. The crimper handles will not open until you apply the proper amount of pressure to the splice sleeve. Repeat steps 4 and 5 for the opposite end of the splice.

    Object Number: 9503  Size: SH
  11. Shrink the Insulation Around the Splice.
  12. • Use the heat torch in order to apply heat to the crimped area of the barrel.
    • 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.

Crimp and Seal Splice Table

Splice Sleeve Color

Crimp Tool Nest Color

Wire Gauge mm² / (AWG)

Salmon (yellow-pink)

Red (1)

0.5-0.8 / (18-20)

Blue

Blue (2)

1.0-2.0 / (14-16)

Yellow

Yellow (3)

3.0-5.0 / (10-12)

SRS Wire Splice Repair

Apply a new splice (not sealed) from the J-38125 Terminal Repair Kit if damage occurs to any of the original equipment splices (three wires or more) in the SRS wiring harness. Carefully follow the instructions included in the kit for proper splice clip application.

Connector Position Assurance (CPA)

The Connector Position Assurance (CPA) is a small plastic insert that fits through the locking tabs of all the SRS electrical connectors. The CPA ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to ensure good contact between the SRS mating terminals.

Terminal Position Assurance (TPA)

The Terminal Position Assurance (TPA) insert resembles the plastic combs used in the control module connectors. The TPA keeps the terminal securely seated in the connector body. Do not remove the TPA from the connector body unless you remove a terminal for replacement.