INTERMITTENT WIRING HARNESS SHORT (REPL. INTERNAL HARNESS). GMC Truck S15 Pickup - 4WD 1993

For 1990-2009 cars

# INTERMITTENT WIRING HARNESS SHORT (REPL. INTERNAL HARNESS)

#### SUBJECT: INTERMITTENT WIRING HARNESS SHORT TO GROUND (REPLACE INTERNAL WIRING HARNESS)

VEHICLES AFFECTED: 1993 "C/K" "S/T" TRUCKS AND "G", "M", "L" VANS

#### CONDITION:

Some 1993 vehicles equipped with the HYDRA-MATIC 4L60-E transmission may blow an ignition fuse which forces the transmission to default into 3rd gear starts when in D4. Possible diagnostic trouble codes (DTC's) 66, 67, 81, and 82 may exist.

CAUSE: (FIGURE 1)

The HYDRA-MATIC 4L60-E transmission built before October 01, 1992 (Julian Date 275) may have a wiring harness that has a wire connector that may short to the valve body.

#### CORRECTION:

Follow the diagnosis procedure in Figure 2.

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.