Rainier AWD V8-5.3L VIN P (2004)
Impact Sensor: Description and Operation
Inflatable Restraint Electronic Frontal Sensor (EFS)
INFLATABLE RESTRAINT ELECTRONIC FRONTAL SENSOR (EFS)
The electronic frontal sensor (EFS) (also known as inflatable restraint front end discriminating sensor) is equipped on some vehicles to supplement the
SIR system performance. The EFS is an electronic sensor (accelerometer) and is not part of the deployment loops, but instead provides an input to the
SDM. The EFS can assist in determining the severity of some frontal collisions. The SDM contains a microprocessor which performs calculations using
the measured accelerations and compares these calculations to a value stored in memory. When the generated calculations exceed the stored value, the
SDM will cause current to flow through the frontal deployment loops deploying the frontal air bags.
