P0137 on GMC Sierra 1500
Factory diagnostic protocol and troubleshooting wire for fault code P0137 specifically for the GMC Sierra 1500 (2020–2026, 5.3L / 6.2L EcoTec3 V8 (Denali 420HP) / 3.0L Duramax Turbo-Diesel).
1. Symptoms of P0137 on GMC Sierra 1500
When the Engine Control Module (ECM/PCM) on your GMC Sierra 1500 (5.3L / 6.2L EcoTec3 V8 (Denali 420HP) / 3.0L Duramax Turbo-Diesel) logs fault code P0137, drivers commonly observe:
2. Most Likely Causes on GMC Sierra 1500
Historical warranty claims and technical repair bulletins for GMC Sierra 1500 point to the following failure distribution:
3. Step-by-Step DIY Repair Guide for GMC Sierra 1500
Listen for exhaust ticking or black soot around flex pipe, flanges, and sensor bungs before the catalytic converter. on the GMC Sierra 1500 equipped with 5.3L / 6.2L EcoTec3 V8 (Denali 420HP) / 3.0L Duramax Turbo-Diesel.
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 GMC Sierra 1500 equipped with 5.3L / 6.2L EcoTec3 V8 (Denali 420HP) / 3.0L Duramax Turbo-Diesel.
Unplug harness, remove old sensor with 7/8 socket, install replacement sensor and plug firmly. on the GMC Sierra 1500 equipped with 5.3L / 6.2L EcoTec3 V8 (Denali 420HP) / 3.0L Duramax Turbo-Diesel.
Clear DTCs and verify B1S2 holds steady between 0.45V and 0.75V during steady highway cruising. on the GMC Sierra 1500 equipped with 5.3L / 6.2L EcoTec3 V8 (Denali 420HP) / 3.0L Duramax Turbo-Diesel.
Equipment for Diagnosing GMC Sierra 1500 (P0137)
GMC Sierra 1500 OEM Replacement Sensor
Direct-fit replacement assembly engineered to OEM tolerances for GMC Sierra 1500.
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 GMC Sierra 1500
Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the GMC Sierra 1500:
4. GMC Sierra 1500 P0137 FAQs
What causes code P0137 to trigger on a GMC Sierra 1500?
On the GMC Sierra 1500 (5.3L / 6.2L EcoTec3 V8 (Denali 420HP) / 3.0L Duramax Turbo-Diesel), 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 GMC Sierra 1500?
On the GMC Sierra 1500, the 16-pin DLC diagnostic connector is located Under driver dashboard, left of steering column. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.
Can I safely drive my GMC Sierra 1500 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.