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2012 Nissan Altima P2101 P0223 P0123 Diagnostic: No Warning Light, Codes Clear Only at Start

Model: 2012 Nissan Altima Fault Code: P0123 Posted: 2017-10-12 19:29

My 2012 Nissan Altima 2.5L engine displays trouble codes P2101, P0223, and P0123. The warning light appears only when starting the vehicle or with the ignition on—there is no illumination while the engine is running. The car runs smoothly under normal conditions. I have successfully cleared these codes using both a code reader and by disconnecting the battery for 30 minutes while keeping headlights on, followed by honking the horn for 30 seconds. Despite clearing the codes, they return intermittently. I am seeking reliable troubleshooting steps to identify the root cause of these persistent issues. Any insights or solutions would be greatly appreciated. Thank you, Ajit S. Dhillon

Related fault codes
P0123P0223P2101
Comments (2)
Anonymous 2017-10-13 08:53

Refer to this forum's detailed trouble code explanations for potential causes and fixes. The issue may stem from intermittent problems with the throttle position sensor or pedal circuit. A recommended troubleshooting step is to unplug and reconnect the relevant connectors to test for loose connections or corrosion.

Anonymous 2017-10-14 13:42

Thanks for the input. It turned out that my original code reader was faulty, which caused false readings. After replacing it with a reliable OBD2 scanner, all codes disappeared and have not returned since.