350SDL (126.135) L6-3.5L DSL Turbo (603.970) (1990)
Air Bag Control Module: Technical Service Bulletins
Airbag - Production Modification SRS Control Unit
REF. NO. 91/43
TO: OUR MERCEDES-BENZ PASSENGER CAR DEALERS
DATE: April 1990
SUBJECT:
A.
MODIFIED SRS CONTROL UNIT
B.
SRS CONTROL UNIT PARTS PROCUREMENT
C.
REVISED SRS TEST CARD
MODELS 107, 124, 126, 129, AND 201
A.
Modified Control Unit
As of July 1989, only SRS control units with a reed contact switch, instead of the previous mercury switch, are installed. (The mercury switch or reed
switch functions as a mechanical "safing sensor" and must close before the electronic sensing system can trigger a deployment).
The modified control units are recognizable by the raised oval on the control unit housing (1, Figure 1).
Important Note:
Defective control units with the raised oval which are out-of-warranty may be discarded without further precautions.
Defective control units without the raised oval (mercury switch) must be returned to MBNA, Warranty Inspection regardless of whether or not warranty
is still in effect. Federal law prohibits the disposal of any mercury product (except as a toxic waste), even in such small quantities as contained in the
control unit's mercury switch. MBNA will assume the responsibility of toxic waste disposal after the mercury has been recovered from the control units.
In-warranty units will be requested for return by MBNA via the Parts Return Request form. Dealers should collect out-of-warranty warranty units and
periodically ship them to MBNA, Warranty Receiving Department.
Control units with the raised oval which are under warranty shall be returned in the usual manner.
B.
SRS Control Unit Parts Procurement