TSB Document:

• Sorry, the NHTSA has not posted this TSB document yet.

You can still get the detailed info from GMC for this TSB. Call your local GMC dealer's service department & ask for a copy of TSB# 3389.

Affected Component: POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE)

Summary

FOUR WHEEL DRIVE INOPERATIVE AND THE 4WD SERVICE LIGHT WILL ILLUMINATE. DIAGNOSIS MAY REVEAL THAT THE ATC FUSE COULD BE OPEN, POSSIBLE DTC C0308, OR VARIOUS U CODES MAY BE SET. THE ENCODER MOTOR MAY ALSO BE SHORTED OR THE TCCM MAY BE DAMAGED. *TT

FOUR WHEEL DRIVE INOPERATIVE AND THE 4WD SERVICE LIGHT WILL ILLUMINATE. DIAGNOSIS MAY REVEAL THAT THE ATC FUSE COULD BE OPEN, POSSIBLE DTC C0308, OR VARIOUS U CODES MAY BE SET. THE ENCODER MOTOR MAY ALSO BE SHORTED OR THE TCCM MAY BE DAMAGED. *TT