Sorry, the NHTSA has not posted this TSB document yet.
You can still get the detailed info from Mercedes-Benz for this TSB. Call your local Mercedes-Benz dealer's service department & ask for a copy of TSB# PB-91-60-189.
MERCEDES: THERE IS A SRS WARNING IN THE INSTRUMENT CLUSTER; THIS MAY BE DUE TO THE WSS CONTROL UNIT CONNECTION BEING LOOSE OR UNPLUGGED. NO MODEL YEARS LISTED. *PE