Transmission and drivelineModel years 2002–2004Manufacturer
4WD/AWD lamps and system inoperative: "sleepy" New Venture Gear transfer case control module (reprogram the TCCM)
Bulletin 02-04-21-006 lists 2002-03 GMC Yukon with the active two-speed transfer case (RPO NP8); the Fix It Right row (02-04-21-006D) is worded by class: 2002-2004 Fullsize and Midsize Pickups and Utilities.
FaultCrate・4WD/AWD lamps and system inoperative: "sleepy" New Venture Gear transfer case control module (reprogram the TCCM)
How to tell
What to do
- As a temporary fix, remove and reinstall the TCCM fuse.
- Verify the sleepy module as the primary cause, then reprogram the TCCM with the latest software.
- Replace the module only if a C0550 DTC shows as current or in history; the reference is bulletin 02-04-21-006D.
Caution
- Do not replace the encoder motor or the transfer case.
Applies to
- Bulletin 02-04-21-006, inoperative 4WD/AWD lamps and inoperative 4WD/AWD system, lists 2002-03 Chevrolet TrailBlazer, Silverado, Tahoe, Suburban, Envoy, Sierra, Yukon and Oldsmobile Bravada with the active two-speed transfer case (RPO NP8).
- Row for 2002-2004 Fullsize and Midsize Pickups and Utilities: sleepy New Venture Gear transfer case control module.
See the evidence (2 documents, 6 passages)
| Document | Publisher | Date |
|---|---|---|
| [1]GM TechLink, September 2002 ↗ | ManufacturerGeneral Motors | 2002-09-01 |
| [2]GM TechLink, February 2005 ↗ | ManufacturerGeneral Motors | 2005-02-01 |
Applies toBulletin 02-04-21-006, inoperative 4WD/AWD lamps and inoperative 4WD/AWD system, lists 2002-03 Chevrolet TrailBlazer, Silverado, Tahoe, Suburban, Envoy, Sierra, Yukon and Oldsmobile Bravada with the active two-speed transfer case (RPO NP8).
02-04-21-006; Inoperative 4WD/AWD Lamps, Inoperative 4WD/AWD System (Remove/Reinstall TCCM Fuse – Temporary Fix); 2002-03 Chevrolet TrailBlazer, Silverado, Tahoe, Suburban, BMC Envoy, Sierra, Yukon, Oldsmobile Bravada with Active Two-Speed Transfer Case (RPO NP8)— [1]
Applies toRow for 2002-2004 Fullsize and Midsize Pickups and Utilities: sleepy New Venture Gear transfer case control module.
2002-2004 Fullsize and Midsize Pickups and Utilities – Sleepy New Venture Gear Transfer Case Control Module— [2]
RepairAs a temporary fix, remove and reinstall the TCCM fuse.
Inoperative 4WD/AWD Lamps, Inoperative 4WD/AWD System (Remove/Reinstall TCCM Fuse – Temporary Fix)— [1]
RepairVerify the sleepy module as the primary cause, then reprogram the TCCM with the latest software.
Verify sleepy module as primary cause. Reprogram TCCM with latest software.— [2]
RepairReplace the module only if a C0550 DTC shows as current or in history; the reference is bulletin 02-04-21-006D.
Replace the module only if a C0550 DTC shows as current or in history. 02-04-21-006D— [2]
CautionDo not replace the encoder motor or the transfer case.
Don’t replace encoder motor or transfer case.— [2]
Put together by FaultCrate from public records and technical documents. The cause and the repair are for the workshop to decide with the vehicle in front of it. Counts are records, not failure rates.
List the records (2 that can be opened)
Records whose recall number, document number or text matches. Each line says why it matched.
- "Sleepy" New Venture Gear transfer case control module: reprogram the TCCMManufacturer communication 2005-02-01・document number matches
- 4WD/AWD lamps and system inoperative (bulletin 02-04-21-006)Manufacturer communication 2002-09-01・document number matches