SERVICE GUILD: CORRECT CABLE INSULATION FOR CABLE (WIRING)

VEHICLES AFFECTED: 1980-89 ALL PASSENGER MODELS

Wiring repairs on a vehicle in an area that is not subjected to high temperatures (i.e. passenger compartment, instrument panel or cargo compartment) may be accomplished using a cable of sufficient size (mm2 or gauge) with a general purpose insulation. The common general purpose cable insulation material is polyvinyl chloride (PVC). PVC insulation should not be used for wiring repairs in areas where temperatures exceed 80 degrees C (176 degrees F).

For wiring repairs in areas where temperatures exceed 80 degrees C (176 degrees F), a cable of sufficient size with a special thermo set compound is required. Cross link polythylene (Insulex (TM)) is such a material and should be used where temperatures exceed 80 degrees C (176 degrees F) such as the engine compartment, especially when the wiring harness is near the exhaust manifold or exhaust system. Cross link polythylene can withstand continuous operating temperatures of up to 148 degrees C (300 degrees F), see Fig. 1, and has 25% more resistance to abrasion and 10% more "pinch" protection than general purpose PVC cable insulation. Should a short occur, the cross link polythylene insulation will not burn.

Insulex (TM) (cross link polythylene) cable is available from .8 mm2 (18 GA) to 13 mm2 (6 GA) and sizes .8 mm2 (18 GA) to 5 mm2 (10 GA) are available in various colours. Bulk insulation cable is available on 50 foot, 100 foot or 1000 foot spools, depending on the cable size.

If a dealership does not want to stock bulk spools of both PVC and Insulex (TM) cable in all of the various sizes, it is recommended to stock only Insulex (TM) cable to help control parts inventory, since Insulex (TM) can be used to replace PVC cable.

Insulex (TM) may not be used to replace the wiring to the throttle body injector connector or to replace wire on a fuel tank unit since gasoline or fuel vapours can damage the polythylene compounds. Insulex (TM) may not be used to replace fusible link cable or to repair the lead on an oxygen sensor due to the extremely high temperature at the oxygen sensor location. Insulex (TM) can be used for all other cable repairs.

The Wire and Terminal Repair Kit (essential tool) J 38125 contains three sizes of crimp and seal splice sleeves, crimping tools, heating torch and an instruction manual which should be used for cable repair. The crimp and seal splice sleeves, like Insulex (TM) cable, are suitable for use in high temperature areas and will provide a good environment seal for the splice.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.