When servicing an ECM on a 1993 truck, the technician may find light grease applied to the connector. The lubricant is applied to aid in the assembly process and will not interfere with electrical connections or have an adverse affect on the ECM, ECM connector, wiring etc.
When diagnosing an ECM or wiring condition, be aware that the lubricant is not the cause. The lubricant used is only to aid the assembly line operator and is not available commercially in small quantities. In any case, in the repair shop environment no lubricant is necessary, therefore, no attempt should be made to substitute lubricant. Substitutes may interfere with electrical connections, deteriorate connectors or wire insulation over time.
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.