VEHICLES AFFECTED: 1993 "C/K" "S/T" TRUCKS AND "G", "M", "L" VANS
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.
Follow the diagnosis procedure in Figure 2.
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