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P0137 on Buick Encore GX

O2 Sensor Circuit Low Voltage (Bank 1 Sensor 2)

Factory diagnostic protocol and troubleshooting wire for fault code P0137 specifically for the Buick Encore GX (2020–2026, 1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP)).

Verified OEM Telemetry & Field Repair Tree
Buick Encore GX2020–2026
Buick Encore GX
SUV1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP)
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
Encore GX SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Drivable (Short Trip)
Low urgency level
Est. Repair Cost
$100 - $300 (DIY: $35 - $100)
Parts & Labor DIY
Check P0137 On Another Buick Model:
Diagnose P0137 on Specific Encore GX Model Year:

1. Symptoms of P0137 on Buick Encore GX

When the Engine Control Module (ECM/PCM) on your Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP)) logs fault code P0137, drivers commonly observe:

Check Engine Light on on Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP))
Downstream sensor voltage consistently below 0.15V on scan tool on Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP))
Failed emissions test on Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP))
Buick Encore GX OBD-II Port Location
The 16-pin diagnostic connector is located Under driver side lower dash near knee panel. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Buick Encore GX

Historical warranty claims and technical repair bulletins for Buick Encore GX point to the following failure distribution:

55%
Exhaust leak upstream of or directly at the Sensor 2 bung letting in fresh air (Buick OEM Part)
25%
Faulty downstream oxygen sensor (Buick OEM Part)
12%
Short to ground in sensor signal wire (Buick OEM Part)
8%
Extremely lean exhaust condition (Buick OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Buick Encore GX.

3. Step-by-Step DIY Repair Guide for Buick Encore GX

01
Inspect Exhaust System for Leaks

Listen for exhaust ticking or black soot around flex pipe, flanges, and sensor bungs before the catalytic converter. on the Buick Encore GX equipped with 1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP).

Required Tool: Flashlight, Jack Stands
02
Check Sensor Signal Voltage with Scan Tool

Monitor B1S2 voltage. Snap the throttle to enrich mixture; voltage should briefly spike above 0.8V. If it remains 0.0V–0.1V, sensor is defective or shorted. on the Buick Encore GX equipped with 1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP).

Required Tool: OBD-II Scanner
03
Replace Downstream O2 Sensor

Unplug harness, remove old sensor with 7/8 socket, install replacement sensor and plug firmly. on the Buick Encore GX equipped with 1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP).

Required Tool: O2 Sensor Socket, Ratchet
04
Clear Codes

Clear DTCs and verify B1S2 holds steady between 0.45V and 0.75V during steady highway cruising. on the Buick Encore GX equipped with 1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP).

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

Equipment for Diagnosing Buick Encore GX (P0137)

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Direct-Fit Replacement Part

Buick Encore GX OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for Buick Encore GX.

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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.

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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 Buick Encore GXVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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Other Common Fault Codes on Buick Encore GX

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Buick Encore GX:

4. Buick Encore GX P0137 FAQs

What causes code P0137 to trigger on a Buick Encore GX?

On the Buick Encore GX (1.2L Turbo 3-Cyl (137HP) / 1.3L Turbo 3-Cyl (155HP)), P0137 is most frequently caused by Exhaust leak upstream of or directly at the Sensor 2 bung letting in fresh air or Faulty downstream oxygen sensor.

Where is the OBD-II port located on my Buick Encore GX?

On the Buick Encore GX, the 16-pin DLC diagnostic connector is located Under driver side lower dash near knee panel. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Buick Encore GX with code P0137?

Yes. Vehicle is fully drivable, but Check Engine Light will remain illuminated. Given that P0137 carries a Low severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.