P0137 on Mazda CX-5
Factory diagnostic protocol and troubleshooting wire for fault code P0137 specifically for the Mazda CX-5 (2020–2026, 2.5L Skyactiv-G (187HP) / 2.5L Dynamic Pressure Turbo (256HP)).
1. Symptoms of P0137 on Mazda CX-5
When the Engine Control Module (ECM/PCM) on your Mazda CX-5 (2.5L Skyactiv-G (187HP) / 2.5L Dynamic Pressure Turbo (256HP)) logs fault code P0137, drivers commonly observe:
2. Most Likely Causes on Mazda CX-5
Historical warranty claims and technical repair bulletins for Mazda CX-5 point to the following failure distribution:
3. Step-by-Step DIY Repair Guide for Mazda CX-5
Listen for exhaust ticking or black soot around flex pipe, flanges, and sensor bungs before the catalytic converter. on the Mazda CX-5 equipped with 2.5L Skyactiv-G (187HP) / 2.5L Dynamic Pressure Turbo (256HP).
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 Mazda CX-5 equipped with 2.5L Skyactiv-G (187HP) / 2.5L Dynamic Pressure Turbo (256HP).
Unplug harness, remove old sensor with 7/8 socket, install replacement sensor and plug firmly. on the Mazda CX-5 equipped with 2.5L Skyactiv-G (187HP) / 2.5L Dynamic Pressure Turbo (256HP).
Clear DTCs and verify B1S2 holds steady between 0.45V and 0.75V during steady highway cruising. on the Mazda CX-5 equipped with 2.5L Skyactiv-G (187HP) / 2.5L Dynamic Pressure Turbo (256HP).
Equipment for Diagnosing Mazda CX-5 (P0137)
Mazda CX-5 OEM Replacement Sensor
Direct-fit replacement assembly engineered to OEM tolerances for Mazda CX-5.
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 Mazda CX-5
Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Mazda CX-5:
4. Mazda CX-5 P0137 FAQs
What causes code P0137 to trigger on a Mazda CX-5?
On the Mazda CX-5 (2.5L Skyactiv-G (187HP) / 2.5L Dynamic Pressure Turbo (256HP)), 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 Mazda CX-5?
On the Mazda CX-5, 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 Mazda CX-5 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.

