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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 -Fig 21 . Accelerate vehicle to 45 MPH and note test light. If test light does not illuminate, problem is a faulty ECM connector or ECM

Fig 1: 2.0L, 2.2L & 2.5L Converter Clutch Schematic (Except 2.5L Lumina)

G90I13183

Courtesy of GENERAL MOTORS CORP.

Fig 2: 2.3L Converter Clutch Schematic (Cutlass Calais, Cutlass Supreme, Grand Am, Grand Prix & Skylark)

G90H13182

Courtesy of GENERAL MOTORS CORP.

Fig 3: 2.5L Converter Clutch Schematic (Lumina)

G90J13184

Courtesy of GENERAL MOTORS CORP.

Fig 4: 3.1L Converter Clutch Schematic (Beretta & Corsica)

G91F07650

Courtesy of GENERAL MOTORS CORP.

Fig 5: 3.1L Converter Clutch Schematic (Camaro & Firebird)

G91B07648

Courtesy of GENERAL MOTORS CORP.

Fig 6: 3.1L Converter Clutch Schematic (Cavalier)

G91D07649

Courtesy of GENERAL MOTORS CORP.

Fig 7: 3.1L Converter Clutch Schematic (6000 With 3T40 Transaxle)

G91H07651

Courtesy of GENERAL MOTORS CORP.

Fig 8: 3.1L Converter Clutch Schematic (6000 With 4T60 Transaxle)

G91J07652

Courtesy of GENERAL MOTORS CORP.

Fig 9: 3.1L Converter Clutch Schematic (Lumina With 3T40 Transaxle)

G91B07653

Courtesy of GENERAL MOTORS CORP.

Fig 10: 3.1L Converter Clutch Schematic (Cutlass Supreme, Grand Prix, Regal & Lumina With 4T60 Transaxle)

G90I13191

Courtesy of GENERAL MOTORS CORP.

Fig 11: 3.3L Converter Clutch Schematic (Century & Skylark With 3T40 Transaxle)

G90J13192

Courtesy of GENERAL MOTORS CORP.

Fig 12: 3.3L Converter Clutch Schematic (Century with 4t60 Transaxle)

G90A13193

Courtesy of GENERAL MOTORS CORP.

Fig 13: 3.8L Converter Clutch Schematic (Bonneville, Eighty-Eight & LeSabre)

G90B13194

Courtesy of GENERAL MOTORS CORP.

Fig 14: 3.8L Converter Clutch Schematic (Ninety-Eight, Park Avenue, Reatta, Riviera, Touring Sedan & Trofeo)

G91D07654

Courtesy of GENERAL MOTORS CORP.

Fig 15: 4.9L Converter Clutch Schematic (Eldorado & Seville)

G91A07657

Courtesy of GENERAL MOTORS

Fig 16: 4.9L Converter Clutch Schematic (DeVille & Fleetwood)

G91C07658

Courtesy of GENERAL MOTORS CORP.

Fig 17: 5.0L TBI Converter Clutch Schematic (Camaro & Firebird)

G90F13198

Courtesy of GENERAL MOTORS CORP.

Fig 18: 5.0L & 5.7L TBI Converter Clutch Schematic (Caprice, Custom Cruiser & Roadmaster)

G91G07655

Courtesy of GENERAL MOTORS CORP.

Fig 19: 5.0L & 5.7L PFI Converter Clutch Schematic (Camaro & Firebird)

G90J13200

Courtesy of GENERAL MOTORS CORP.

Fig 20: 5.7L Converter Clutch Schematic (Brougham)

G90A13201

Courtesy of GENERAL MOTORS CORP.

Fig 21: 5.7L Converter Clutch Schematic (Corvette)

G90B13202

Courtesy of GENERAL MOTORS CORP.