B0091 on Lexus NX
Factory diagnostic protocol and troubleshooting wire for fault code B0091 specifically for the Lexus NX (2022–2026, 2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP)).
1. Symptoms of B0091 on Lexus NX
When the Engine Control Module (ECM/PCM) on your Lexus NX (2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP)) logs fault code B0091, drivers commonly observe:
2. Most Likely Causes on Lexus NX
Historical warranty claims and technical repair bulletins for Lexus NX point to the following failure distribution:
3. Step-by-Step DIY Repair Guide for Lexus NX
Disconnect battery negative cable and wait 15 minutes to fully discharge SRS backup capacitors before touching airbag components. on the Lexus NX equipped with 2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP).
Remove driver side door sill trim / lower B-pillar trim to access the yellow impact sensor. on the Lexus NX equipped with 2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP).
Inspect sensor for water corrosion or cracked plastic housing. on the Lexus NX equipped with 2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP).
Bolt new OEM side impact sensor into clean, rust-free ground location, torque bolt to spec, and click yellow locking connector firmly. on the Lexus NX equipped with 2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP).
Reconnect battery, clear SRS trouble codes with an airbag-capable scanner, and verify light turns off after 5-second bulb check. on the Lexus NX equipped with 2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP).
Equipment for Diagnosing Lexus NX (B0091)
Lexus NX OEM Replacement Sensor
Direct-fit replacement assembly engineered to OEM tolerances for Lexus NX.
AstroAI Auto-Ranging Digital Multimeter
Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.
BlueDriver Bluetooth Pro OBDII Scan Tool
Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.
Other Common Fault Codes on Lexus NX
Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Lexus NX:
4. Lexus NX B0091 FAQs
What causes code B0091 to trigger on a Lexus NX?
On the Lexus NX (2.5L 4-Cyl / 2.4L Turbo (275HP) / 2.5L Hybrid (NX 350h) / PHEV (NX 450h+ 304HP)), B0091 is most frequently caused by Corroded or damaged left side impact crash sensor (B-pillar or door sill) or Corroded wiring harness under driver seat / driver door sill.
Where is the OBD-II port located on my Lexus NX?
On the Lexus NX, the 16-pin DLC diagnostic connector is located Under driver dash near footwell illumination lamp. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.
Can I safely drive my Lexus NX with code B0091?
Caution. Side curtain and seat airbag deployment may be disabled in a side-impact collision. Given that B0091 carries a Critical severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.

