DTC U3000 Sym49 Set In The Serial Data Gateway Module (PIT6398)

DTC U3000 SYM49 SET IN THE SERIAL DATA GATEWAY MODULE

TECHNICAL SERVICE BULLETIN

SERVICE INFORMATION

Brand:	Model:	Model Year:		VIN:		Engine:	Transmission:
		from	to	from	to
Cadillac	CT4	2021-2023		All	All	All	All
Cadillac	CT5	2021-2023		All	All	All	All
Cadillac	Escalade	2021-2023		All	All	All	All
Cadillac	Escalade ESV	2021-2023		All	All	All	All
Chevrolet	Silverado 2500	2024-2025		All	All	All	All
Chevrolet	Silverado 3500	2024-2025		All	All	All	All
Chevrolet	Suburban	2021-2023		All	All	All	All
Chevrolet	Tahoe	2021-2023		All	All	All	All
Chevrolet	Corvette	2021-2022		All	All	All	All
GMC	Sierra 2500	2024-2025		All	All	All	All
GMC	Sierra 3500	2024-2025		All	All	All	All
GMC	Yukon	2021-2023		All	All	All	All
GMC	Yukon XL	2021-2023		All	All	All	All

Involved Region or Country	North America
Condition	When inspecting for DTC's, a U3000 sym49 may be set as current in the K56 Serial Data Gateway Module (SDGM). In some cases, there could be a low or dead battery condition.
Cause	This is due to a false internal performance fault.

CORRECTION

Before continuing with further diagnostics, perform a reset to the K56 SDGM by disconnecting the battery for several minutes, reconnecting it, and then clearing DTC's. Do not replace the K56 SDGM if the DTC does not return as current. If DTC U3000 SYM49 persists as current, continue with normal SI diagnostics.

WARRANTY INFORMATION

For vehicles repaired under the Bumper-to-Bumper coverage (Canada Base Warranty coverage), use the following labor operation. Reference the Applicable Warranties section of Investigate Vehicle History (IVH) for coverage information.

Labor Operation	Description	Labor Time
2081228*	Reset the K56 SDGM by disconnecting the battery for several minutes then reconnecting and clearing DTC's	0.3 Hrs
*This is a unique Labor Operation for Bulletin use only.

Version	1
Modified	06/12/20252 - Created