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Home >> GMC >> 1998 >> Forward Control 6.5 F >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 2 (Engine Controls - Tests W/Codes - 4.3L) >> Diagnostic Trouble Codes >> Notes
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Diagnostic Trouble Codes: Notes

WARNING: This page is about a different variant/trim than selected.
NOTE: Before clearing DTCs, perform procedures under POWERTRAIN ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK . Record FREEZE FRAME and FAILURE RECORDS for reference during testing. Data will be erased when DTCs are cleared. If ECM/PCM/VCM is replaced, NEW ECM/PCM/VCM must be programmed using special manufacturer's equipment.