Sorry, the NHTSA has not posted this TSB document yet.
You can still get the detailed info from Cadillac for this TSB. Call your local Cadillac dealer's service department & ask for a copy of TSB# PIE-0042A.
Affected Component: POWER TRAIN:TRANSFER CASE (4-WHEEL DRIVE)
GMC/CADILLAC/CHEVROLET: ENGINEERING INFORMATION-SERVICE 4 WHEEL DRIVE MESSAGE DISPLAYED. GM ENGINEERING ATTEMPTING TO DETERMINE THE ROOT CAUSE OF THE SERVICE 4 WHEEL DRIVE MESSAGE. PRIOR TO REMOVAL OR REPLACEMENT OF THE TRANSFER CASE CONTROL MODULE. *PE
