GM TechLink 2006-12-01
Original text and source
Original text
Transfer Case Won’t Shift
This information applies to 1999-2007 Cadillac Escalade, Chevrolet Avalanche, Trailblazer, Colorado, Blazer, S10, Silverado, Suburban, Tahoe, GMC Canyon, Envoy, Sierra, Yukon, Yukon Denali, Yukon XL, Jimmy, Sonoma, Suburban, Hummer H2 and H3 with RPO NR4, NP1, or NP8 Transfer Case.
The electronic transfer case may stop shifting and not set any DTCs.
This condition will occur if the transfer case control module senses repeated shift requests in a short period of time.
The software in the transfer case control module has a shift abuse lock out mode to protect the module and encoder motor.
If the driver tries to shift into and out of different modes continuously, the transfer case control module will stop trying to shift for several seconds to prevent abuse damage to occur.
Cycling the ignition off for 30 seconds or more should allow the transfer case to resume normal operation.
Source
- Source
- GM TechLink — Communication from a manufacturer to dealers (summary published by a government agency)
- Reporter type
- Manufacturer
- Source reference
- 2006-12-01
- Country / market
- US
- Language
- en
- Document version
- Version 3 (3 held)
- Note on the source
- Copyright General Motors Corporation. No licence is stated. Held as the headline and short quoted passages with the issue named and linked; the articles themselves are not stored or shown.
Dates
- Incident date
- Unknown
- Received by source
- 2006-12-01
- Added to the source's file
- Unknown: not returned by the source API
- Issued / published
- 2006-12-01
- First observed
- 2026-10-06 08:58 UTC (initial bulk load)
- This version fetched
- 2026-10-09 12:52 UTC