Diagnostic Aids

Clear codes and re-check for DTC 39. If DTC 39 resets, problem may be inside torque converter or transmission. DTC 39 will only set in 3rd gear. TCC slip in 4th gear will set DTC 68.

Fig 1: DTC 39 Schematic - 1993 "C", "K" & "P" Series

Courtesy of GENERAL MOTORS CORP.

Fig 2: DTC 39 Schematic - 1993 "G" Series

Courtesy of GENERAL MOTORS CORP.

Fig 3: DTC 39 Flow Chart - 1993

Courtesy of GENERAL MOTORS CORP.