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B0091 on Hyundai Tucson

Left Side Restraints Sensor 1

Factory diagnostic protocol and troubleshooting wire for fault code B0091 specifically for the Hyundai Tucson (2021–2026, 2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP)).

Verified OEM Telemetry & Field Repair Tree
Hyundai Tucson2021–2026
Hyundai Tucson
SUV2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP)
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
Tucson SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Drivable (Short Trip)
Critical urgency level
Est. Repair Cost
$150 - $450 (DIY: $60 - $180)
Parts & Labor DIY
Check B0091 On Another Hyundai Model:
Diagnose B0091 on Specific Tucson Model Year:

1. Symptoms of B0091 on Hyundai Tucson

When the Engine Control Module (ECM/PCM) on your Hyundai Tucson (2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP)) logs fault code B0091, drivers commonly observe:

Supplemental Restraint System (SRS) / Airbag warning light illuminated on Hyundai Tucson (2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP))
'Service Airbag' message on dashboard instrument cluster on Hyundai Tucson (2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP))
Hyundai Tucson OBD-II Port Location
The 16-pin diagnostic connector is located Driver footwell directly above brake pedal. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Hyundai Tucson

Historical warranty claims and technical repair bulletins for Hyundai Tucson point to the following failure distribution:

55%
Corroded or damaged left side impact crash sensor (B-pillar or door sill) (Hyundai OEM Part)
25%
Corroded wiring harness under driver seat / driver door sill (Hyundai OEM Part)
12%
Loose or unseated yellow SRS connector plug (Hyundai OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Hyundai Tucson.

3. Step-by-Step DIY Repair Guide for Hyundai Tucson

01
Disconnect Vehicle Battery

Disconnect battery negative cable and wait 15 minutes to fully discharge SRS backup capacitors before touching airbag components. on the Hyundai Tucson equipped with 2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP).

Required Tool: 10mm Wrench
02
Locate Left Side Impact Sensor

Remove driver side door sill trim / lower B-pillar trim to access the yellow impact sensor. on the Hyundai Tucson equipped with 2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP).

Required Tool: Trim Removal Tools, Torx Set
03
Inspect Wiring & Sensor Housing

Inspect sensor for water corrosion or cracked plastic housing. on the Hyundai Tucson equipped with 2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP).

Required Tool: Flashlight
04
Replace Side Impact Sensor

Bolt new OEM side impact sensor into clean, rust-free ground location, torque bolt to spec, and click yellow locking connector firmly. on the Hyundai Tucson equipped with 2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP).

Required Tool: Torx T30 Socket, Torque Wrench
05
Reconnect Battery and Clear SRS Codes

Reconnect battery, clear SRS trouble codes with an airbag-capable scanner, and verify light turns off after 5-second bulb check. on the Hyundai Tucson equipped with 2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP).

Required Tool: SRS-Capable OBD-II Scanner
Recommended Parts & Testing Tools

Equipment for Diagnosing Hyundai Tucson (B0091)

Prime Fast Delivery & Verified Fitment
Direct-Fit Replacement Part

Hyundai Tucson OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for Hyundai Tucson.

$45 – $95 Prime
Check Fitment on Amazon
Sensor Signal Voltage Meter

AstroAI Auto-Ranging Digital Multimeter

4.6 / 5.0 (Best Seller)

Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.

$29.99 Prime
View on Amazon
Top Mobile OBD-II Scanner

BlueDriver Bluetooth Pro OBDII Scan Tool

4.7 / 5.0 (50,000+ Reviews)

Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

Compare OEM & Aftermarket Replacement Sensors for Hyundai TucsonVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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Other Common Fault Codes on Hyundai Tucson

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Hyundai Tucson:

4. Hyundai Tucson B0091 FAQs

What causes code B0091 to trigger on a Hyundai Tucson?

On the Hyundai Tucson (2.5L Smartstream 4-Cyl (187HP) / 1.6L Turbo Hybrid (226HP) / PHEV (261HP)), 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 Hyundai Tucson?

On the Hyundai Tucson, the 16-pin DLC diagnostic connector is located Driver footwell directly above brake pedal. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Hyundai Tucson 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.