INTERMITTENT ECM CONNECTION MAY BE WEAK TERMINAL GRIP

MODELS: 1988 ALL TRUCKS EQUIPPED WITH ECMS

Some 1988 Trucks equipped with ECMs may experience a condition in which the female terminals in the connector to the ECM do not make a solid connection to the male pins in the ECM (see illustration). This can result in an intermittent condition, in any circuit operated by the ECM. The Driveability and Emissions Manual directs a check of connections any time an intermittent condition is found. Example: "Service Engine Soon" light on but no trouble codes are stored in the ECM. This may be the cause of some of these conditions.

If this condition exists, visually inspect the terminal using a flashlight, or use a .95mm pin gage, The gage should not pass freely through the female terminal. Do not probe the terminal with anything other tban tbe pin gage, as probing could damage the terminal. If the female terminal does not grip properly, replace the terminal with P/N 12020757. General directions on wiring repair are shown on page 3-92 thru 3-94 of the 1988 Driveability and Emissions Manual X-8836.

For vehicles repaired under warranty use:

LaborOperation: N6278 Labor Time: .5 hr

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.