Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
P0135 - O2 Heater Circuit (Bank 1, Sensor 1)
2010 Mercury Mariner Hybrid, AWDSECTION P0135 - O2 Heater Circuit (Bank 1, Sensor 1)
WARNING: This page is about a different car, the 2007 Mercury Mariner and 2007 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
P0135 - O2 HEATER CIRCUIT (BANK 1, SENSOR 1)
| Description: | During testing the heated oxygen sensor (HO2S) heaters are checked for open and short circuits and excessive current draw. The test fails when the current draw exceeds a calibrated limit or an open or short circuit is detected. | |||
| Possible Causes: |
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| Diagnostic Aids: | Inspect the sensor, wiring, and connectors for damage, corrosion, or water intrusion. | |||
| Application | Key On Engine Off | Key On Engine Running | Continuous Memory | |
| All | refer to PINPOINT TEST DW . | |||
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.