SIR SENSOR REPLACE POLICY REV. ALL 1988-92 CARS WITH SIR

SUBJECT: SIR SENSOR REPLACEMENT POLICY REVISED

VEHICLES AFFECTED: ALL 1988 - 1992 CARS WITH SIR

General Motors has revised its policy on replacement of SIR sensors. Until now, all system sensors were replaced after an SIR deployment event. The new replacement policy specifies mandatory replacement of the sensors in the area of accident damage only.

The "area of accident damage" is defined as that area of the vehicle which is crushed, bent, or damaged in other ways. An example might be a front-end collision in which the forward portions of the vehicle have contacted another vehicle, tree, guardrail, etc. In this example, sensor(s) on the radiator tie bar would require replacement, since that portion of the vehicle was damaged in the accident. Sensors in the passenger compartment, such as the Passenger Compartment Discriminating Sensor, the Arming Sensor, or the Dual Sensor (if equipped), would not require mandatory replacement. Of course, if the DERM sets a code and the diagnostic chart leads to a faulty sensor that was not in the area of accident damage, that sensor should also be replaced.

Sensors in the area of accident damage should be replaced even if those sensors do not appear to be damaged. Do not attempt to determine whether a sensor is OK--ALWAYS replace it if it is in the area of accident damage.

Exceptions to the new policy are:

- Corvette and GEO Metro (Sprint/Firefly) Convertible. These vehicles still require all sensors to be replaced after a deployment-level collision.

- 1988-1991 Oldsmobile 88 (H-Body) and 1989 and 1990 Oldsmobile 98 (C-Body). These Oldsmobile vehicles used a different SIR system in these model years. Service manual instructions for those model year vehicles should be followed for SIR inspections and repairs after accidents.

Also, if a sensor is in an area of accident damage, but the SIR system has NOT been deployed, replace the sensor. The sensor bracket may be slightly bent, wiring may be damaged, etc., and the sensor might not work properly in another collision. Again, do not attempt to determine whether a sensor is OK -- ALWAYS replace it if it is in the area of accident damage.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.