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.

2021 Honda Insight TouringFACTORY OEM SERVICE PROCEDURE

DTC P2A00: General Description

Courtesy of HONDA, U.S.A., INC.

The air/fuel ratio (A/F) sensor (sensor 1) has a linear signal output in relation to the oxygen concentration. The powertrain control module (PCM) computes the air/fuel ratio from the A/F sensor (sensor 1) output voltage and uses fuel feedback control to improve exhaust emissions. The PCM monitors the A/F sensor (sensor 1) output voltage during deceleration with the throttle fully closed, and if the output voltage deviates greatly from normal oxygen concentration levels, it detects a malfunction and stores a DTC.

NOTE: Output to the scan tool exhibits a relationship between the A/F sensor (sensor 1) output and oxygen concentration, which is opposite to the characteristic shown in the graph. That is, a deviation toward the rich side increases the output voltage and one toward the lean side decreases the output voltage, as the stoichiometric ratio is 0.

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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.