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Torque Converter Clutch (TCC) Solenoid

Disconnect harness connector to TCC solenoid. Measure resistance between TCC solenoid terminals "A" and "D". See Fig 1-Fig 4 . Solenoid resistance should be greater than 20 ohms.

Fig 1: Torque Converter Clutch Schematic (2.5L)
G90A15750Courtesy of GENERAL MOTORS CORP.
Fig 2: Torque Converter Clutch Schematic (3.1L)
G90C15752Courtesy of GENERAL MOTORS CORP.
Fig 3: Torque Converter Clutch Schematic (4.3L Turbo PFI)
G91F13727Courtesy of GENERAL MOTORS CORP.
Fig 4: Torque Converter Clutch Schematic (4.3L, 5.0L & 5.7L Under 8500 GVWR)
G90B15751Courtesy of GENERAL MOTORS CORP.
NOTE: Some solenoids have an internal pressure switch in series with the solenoid winding and will not show continuity until transmission hydraulic pressure is applied. See Fig 2.