TACH ORANGE/RED BARS FLICKER (CHECK BULB/INSTALL CLUSTER)

SUBJECT: TACHOMETER ORANGE/RED BARS FLICKER INTERMITTENTLY (CHECK BULB/INSTALL EXCHANGE CLUSTER)

VEHICLES AFFECTED: 1991-92 "S/T" TRUCKS

The Orange and Red bars on the tachometer for the digital cluster (U52) on some 1991-92 S/T Trucks may flicker intermittently. The cause may be the result of build up of solder on the circuit board pad or a loose bulb or broken bulk filament. The light source for these particular bars are separate from the vacuum florescent portion of the tachometer.

First determine if the flicker condition is caused by a bulb problem. If the bulb checks out good, then an exchange cluster is required,. Delco Electronics issued a bulletin to their repair centres regarding this condition. The exchanged cluster should have been inspected for this condition by the repair centre.

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.