Satellite Sensor – Function, Symptoms, Location, Diagnosis, and Possible DTCs

The Satellite Sensor is an external crash sensor used in many Supplemental Restraint System (SRS) designs. It detects impact forces closer to the point of collision and immediately sends crash information to the Airbag Control Module (ACM), helping improve airbag deployment speed and accuracy.

What Is a Satellite Sensor?

Satellite Sensor = External Crash Sensor (Remote Impact Sensor)

Main Functions

• Detects collision forces at specific areas of the vehicle.
• Sends crash information to the Airbag Control Module.
• Improves airbag deployment timing.
• Works with front, side, and rollover sensors.

Common Symptoms

• Airbag warning light ON.
• SRS diagnostic trouble codes.
• Communication errors with the ACM.
• Impact sensor circuit faults.

Typical Locations

• Front radiator support.
• Behind the front bumper.
• B-pillars.
• Inside front or rear doors.
• Rear body structure.

Simple Signal Diagram

 Vehicle Impact
       │
       ▼
+----------------------+
|  Satellite Sensor    |
+----------------------+
       │ Crash Signal
       ▼
+----------------------+
| Airbag Control Module|
|        (ACM)         |
+----------------------+
       │
       ▼
 Airbags / Pretensioners

Possible Diagnostic Trouble Codes (DTCs)

• B0090–B0093 – Side Impact Sensor Faults
• B1620 – Impact Sensor Circuit Fault
• B1621 – Impact Sensor Signal Fault
• B1622 – Impact Sensor Communication Fault
• B1623 – Impact Sensor Internal Failure
• Manufacturer-specific SRS communication codes

Diagnosis Tips

• Read SRS fault codes using a professional scan tool.
• Inspect the sensor connector and wiring.
• Check for collision damage or water intrusion.
• Verify power and ground according to the service manual.
• Replace the sensor if an internal failure is confirmed.

Important Note

The number, location, connector pinout, communication method (hard-wired or CAN/LIN), and diagnostic trouble codes of Satellite Sensors vary significantly between vehicle manufacturers and models. Always consult the factory service information before testing or replacing any SRS component.

Related SRS Components

• FIS – Front Impact Sensor
• LFIS – Left Front Impact Sensor
• RFIS – Right Front Impact Sensor
• LSIS – Left Side Impact Sensor
• RSIS – Right Side Impact Sensor
• Rear Impact Sensor
• Airbag Control Module (ACM)

Frequently Asked Questions

What is the purpose of a Satellite Sensor?

It detects crash forces near the impact point and sends rapid collision data to the Airbag Control Module.

Can a faulty Satellite Sensor turn on the airbag warning light?

Yes. A malfunction can trigger the SRS warning light and store diagnostic trouble codes.

Are all impact sensors called Satellite Sensors?

No. Many manufacturers refer to front, side, or rear remote crash sensors as Satellite Sensors, while others use different terminology.