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.
Code 29
Condition is: main oxygen sensor signal is more than 0.5 volt and sub-oxygen sensor signal is less than 0.5 volt with engine temperature more than 176°F (80°C), engine speed more than 1500 RPM and accelerator pedal fully depressed for 2 seconds. Probable cause: open or short in heater circuit of sub-heated oxygen sensor (right bank), defective sub-heated oxygen sensor (right bank) or defective ECM.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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.