B0101: Electronic Frontal Sensor 2 Malfunction
6 vehicles · 5 makes
Most Reported On
B0101 is an OBD-II diagnostic trouble code meaning “Electronic Frontal Sensor 2 Malfunction.” The secondary electronic frontal crash sensor has a fault. This code is most commonly reported on 2020-2022 Toyota RAV4 (All, Hybrid), 2010-2016 Toyota 4Runner, and 2007-2013 Hyundai Elantra, plus 3 other vehicles.
Common Causes
Diagnostic Tools
To diagnose B0101, you'll need an OBD-II scanner. Here are our recommendations at every price point.
ANCEL AD310 Classic OBD-II Scanner
by ANCEL
A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).
- Read & clear engine codes
- View freeze frame data
- I/M readiness status
- No batteries or app needed
BlueDriver Pro Bluetooth Scanner
by BlueDriver
Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.
- Enhanced diagnostics (ABS, SRS, transmission)
- Repair Reports with verified fixes
- Smog check readiness
- Free app (iOS & Android)
LAUNCH CRP123X OBD-II Scanner
by LAUNCH
A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.
- Engine, transmission, ABS, SRS diagnostics
- Live data stream & graphing
- AutoVIN for vehicle identification
- Free lifetime updates via Wi-Fi
Autel MaxiCOM MK808S Diagnostic Tool
by Autel
Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.
- All-system diagnostics (25+ modules)
- Bi-directional control & active tests
- Oil reset, EPB, BMS, TPMS, injector coding
- 7-inch touchscreen with Android OS
As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.
Vehicles Affected (6)
FAQ
What does B0101 mean?
B0101 stands for "Electronic Frontal Sensor 2 Malfunction." The secondary electronic frontal crash sensor has a fault.
What are the most common causes of B0101?
The most common causes of B0101 are: Failed sensor, Wiring issue, Connector damage, Impact damage, SRS control module fault. The specific cause varies by vehicle.
How much does it cost to fix B0101?
Repair costs vary widely depending on the root cause and vehicle.
Which vehicles are affected by B0101?
Au7o has documented B0101 across 6 vehicle models from 5 manufacturers: Chevrolet, Hyundai, Jeep, Kia, Toyota.
Sources (12)
- mediaNBC News: Toyota recalling 1.12 million vehicles over potential air bag issue
- mediaWOAY: Toyota recalls nearly 1 million vehicles due to potential defective airbag sensor
- mediaWTVR: Toyota recalls 1 million vehicles over airbag sensor glitch
- mediaRecall Explained: Toyota RAV4 recalls and NHTSA complaint data
- ForumRAV4 World: New RECALL for 2020-2021 RAV4s
- manufacturerToyota Pressroom: Toyota is conducting final phase of Takata airbag safety recall
- manufacturerToyota: Look up Safety Recalls & Service Campaigns by VIN (Takata)
- mediaConsumer Reports: Toyota Recall to Replace Airbags Again | Takata
- ForumToyota 4Runner Forum: Takata Airbag Recall
- manufacturerToyota: DO NOT DRIVE Advisory for Certain 2003-2005 Models with Recalled Takata Airbags
- otherCarProblemZoo: Hyundai Elantra Front Air Bag Sensor Control Problems
- otherJustia: Hyundai Elantra 2007 Air Bags Sensor/Control Module Recall 11V179000
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.