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Home >> Cadillac >> 1999 >> Catera V6-3.0L VIN R >> Repair and Diagnosis >> Powertrain Management >> Relays and Modules - Powertrain Management >> Relays and Modules - Computers and Control Systems >> Engine Control Module >> Description and Operation >> Serial Data
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Serial Data

The Catera uses ISO serial data and communicates with the scan tool on DLC pin-7. Most other GM OBD II vehicles use Class 2 serial data on DLC pin-2. Both the ECM and the TCM communicate with the scan tool by using the ISO serial data circuit.
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