What does this code mean?
The wording below belongs to the named make and communication. Match the complete code, reporting module, model year and engine before applying it.
A code identifies a detected condition, not a part that must automatically be replaced.
Manufacturer communications
2Original wording in English
AM GENERAL, BUICK, CADILLAC, CHEVROLET, GMC, OLDSMOBILE, PONTIAC
Reported code forms B1780
DIAGNOSTIC TROUBLE CODES B1001, B1271 OR B1780 SET WHEN REPLACING / REPROGRAMMING OTHER MODULES FOR 1999 - 2003 PASSENGER CARS AND TRUCKS WITH CLASS 2 SERIAL DATA COMMUNICATION BETWEEN MODULES. *TT
BUICK, CADILLAC, CHEVROLET, GMC, OLDSMOBILE, PONTIAC
Reported code forms B1780
DTCS B1001,B1271 OR B1780 SET WHEN REPLACING /REPROGRAMMING OTHER MODULES. (MODELS FROM 1999-2002 ALL PASSENGER CARS AND TRUCKS) *YH
Check vehicle applicability
1A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
| Make | Model | Model year |
|---|---|---|
| GMC | GMC | Year not specified |
Before replacing a part
Record codes and freeze-frame data. Check battery condition, related codes and visible wiring or hose damage. Follow the vehicle's diagnostic procedure and test results before replacing parts.
Can I keep driving?
A code alone cannot establish whether driving is safe. A flashing malfunction light, severe shaking, overheating, oil-pressure warning or loss of braking or steering needs prompt attention. Stop in a safe place and seek assistance when control or engine safety is affected. Follow the vehicle handbook.