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Home >> Fiat >> 2021 >> 500X Pop >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> 1.3L - DTCS P0121 To P02EE >> DTC Troubleshooting >> P0140-O2 Sensor 1/2 Signal Inactive >> Possible Causes
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Possible Causes

Possible Causes
EXHAUST LEAK
O2 SENSOR 1/2 SIGNAL CIRCUIT
O2 SENSOR 1/2 RETURN CIRCUIT
O2 SENSOR 1/2

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to  PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE  .