P0122 OBD2 Code Still Appearing After Replacing Throttle Position Sensor on 1997 Oldsmobile Regency
After replacing the Throttle Position Sensor (TPS) on my 1997 Oldsmobile Regency, the P0122 code (Throttle Position Sensor Circuit Low Voltage) continues to appear. I'm seeking help to understand why this is happening and what steps I should take next. The OBD2 diagnostic tool shows only this code currently. Could there be a wiring issue or a reference voltage problem? I'd also like confirmation on whether other related codes (such as P163x) might be present, and if my scanner reads all stored fault codes.
A common misconception is that an OBD2 code means a faulty part — in reality, the code only indicates a problem within the system, not necessarily a defective component. P0122 specifically refers to a low voltage issue in the Throttle Position (TP) Sensor circuit. To troubleshoot effectively: - Check if there are any additional diagnostic codes (such as P163x). - Confirm whether your OBD2 scanner reads all stored fault codes. - Measure the actual sensor signal voltage — it should typically be around 0.5V to 4.5V depending on throttle position. - Verify that the 5V reference voltage is present at the TPS connector, as a missing or weak reference can cause incorrect readings. For more details, refer to: http://www.obd-codes.com/p0122