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Converter Lock-Up Signal From ECM

Warm engine to operating temperature. Raise vehicle and support drive wheels. Support suspension where necessary to prevent damage to drive axles.
Connect a test light to battery voltage. Touch TCC control driver terminal with test light. On some vehicles, this is terminal "F" of the ALDL connector. See Fig 1-22. Accelerate vehicle to 45 MPH and note test light. If test light does not illuminate, problem is a faulty ECM connector or ECM.

NOTE: In the following schematics, Assembly Line Data Link (ALDL) connector is also referred to by manufacturer as Data Link Connector (DLC).

Fig 1: Converter Clutch Schematic (3.1L "J" Body)

G91D07649

Courtesy of GENERAL MOTORS CORP.

Fig 2: Converter Clutch Schematic (3.1L "L" Body)

G91F07650

Courtesy of GENERAL MOTORS CORP.

Fig 3: Converter Clutch Schematic (3.1L "W" Body W/3T40 Trans.)

G91B07653

Courtesy of GENERAL MOTORS CORP.

Fig 4: Converter Clutch Schematic (3.1L Fed. & 3.4L "W" Body W/4T60 Trans.)

G92I05469

Courtesy of GENERAL MOTORS CORP.

Fig 5: Converter Clutch Schematic (3.1L "W" Body W/4T60 Trans.- Calif.)

G93A39578

Courtesy of GENERAL MOTORS CORP.

Fig 6: Converter Clutch Schematic (3.3L "A" Body W/3T40 Trans.)

G93B39579

Courtesy of GENERAL MOTORS CORP.

Fig 7: Converter Clutch Schematic (3.3L "A" Body W/4T60 Trans.)

G91G07434

Courtesy of GENERAL MOTORS CORP.

Fig 8: Converter Clutch Schematic (3.3L "N" Body)

G93E39580

Courtesy of GENERAL MOTORS CORP.

Fig 9: Converter Clutch Schematic (3.4L "F" Body)

G93F39581

Courtesy of GENERAL MOTORS CORP.

Fig 10: Converter Clutch Schematic (3.8L "C" & "H" Bodies)

G93I39584

Courtesy of GENERAL MOTORS CORP.

Fig 11: Converter Clutch Schematic (3.8L "E" Body)

G93G39582

Courtesy of GENERAL MOTORS CORP.

Fig 12: Converter Clutch Schematic (3.8L "W" Body)

G93H39583

Courtesy of GENERAL MOTORS CORP.

Fig 13: Converter Clutch Schematic (4.3L - "B" Body)

G91G07655

Courtesy of GENERAL MOTORS CORP.